[PATCHSET 03/03] add hotplug support, take 5

[PATCHSET 03/03] add hotplug support, take 5

[Tejun Heo]

Hello,

This is part of patchset series described in [T].

This is the fifth take of add-hotplug-support patchset.  Changes from
the last take[L] are.

* ata_scsi_hotplug() requeue condition check has been updated such
  that SCSI devices are guaranteed to be attached to ATA devices.  No
  race window anymore.

* boot probing reimplemented using ata_port_wait_eh().

* ata_port_detach() reimplemented using ata_port_wait_eh().  New
  implementation is much more robust and survives PCI unplugging under
  all circumstances.  EH part of unloading is also reimplemented in
  simpler and more robust way.

* UNLOADING check added to ata_scsi_hotplug().  hotplug task flushing
  is reliable now.

* s/FIS34/D2H FIS/g

One thing to note about unload handling is that, if EH is scheduled
after ata_port_detach() is complete but before SCSI host is actually
released, it can oops accessing ap->host_set.  The problem is that, as
SCSI doesn't supply host release callback, host_set is released before
all ports are released.

However, this condition is unlikely to occur - to trigger the bug,
either the driver has to schedule EH while frozen during that window,
or the user has to hold reference to scan/delete node and issue warm
plug request, again, during the window.

This patchset is against

  upstream (ef2824073fba9def3cf122e89cc485f66dd71f70)
  + [1] set-PIO-0-after-successful-EH-reset
  + [2] shift-host-flag-constants
  + [3] implement-ata_eh_wait
  + [4] prep-for-hotplug-support patchset
  + [5] prep-LLDDs-for-hotplug-support patchset

Thanks.

--
tejun

[T] http://article.gmane.org/gmane.linux.ide/11012
[L] http://article.gmane.org/gmane.linux.ide/10892
[1] http://article.gmane.org/gmane.linux.ide/10890
[2] http://article.gmane.org/gmane.linux.ide/11010
[3] http://article.gmane.org/gmane.linux.ide/11011
[4] http://article.gmane.org/gmane.linux.ide/11014
[5] http://article.gmane.org/gmane.linux.ide/11028

[PATCH 03/13] libata-hp: implement SCSI part of hotplug

[Tejun Heo]

Implement SCSI part of hotplug.

This must be done in a separate context as SCSI makes use of EH during
probing.  SCSI scan fails silently if EH is in progress.  In such
cases, libata pauses briefly and retries until every device is
attached.

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

---

 drivers/scsi/libata-core.c |    1 
 drivers/scsi/libata-eh.c   |    6 ++
 drivers/scsi/libata-scsi.c |  116 ++++++++++++++++++++++++++++++++++++++++++++
 drivers/scsi/libata.h      |    1 
 include/linux/libata.h     |    2 -
 5 files changed, 124 insertions(+), 2 deletions(-)

580b2102327ab8444af5bde4e70b50d268a1d558
diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index c965eea..8df8ecc 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -5370,6 +5370,7 @@ static void ata_host_init(struct ata_por
 	ap->msg_enable = ATA_MSG_DRV;
 
 	INIT_WORK(&ap->port_task, NULL, NULL);
+	INIT_WORK(&ap->hotplug_task, ata_scsi_hotplug, ap);
 	INIT_LIST_HEAD(&ap->eh_done_q);
 	init_waitqueue_head(&ap->eh_wait_q);
 
diff --git a/drivers/scsi/libata-eh.c b/drivers/scsi/libata-eh.c
index b53e2e7..733dfa5 100644
--- a/drivers/scsi/libata-eh.c
+++ b/drivers/scsi/libata-eh.c
@@ -287,9 +287,13 @@ void ata_scsi_error(struct Scsi_Host *ho
 	/* 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");
-	ap->flags &= ~ATA_FLAG_RECOVERED;
+
+	ap->flags &= ~(ATA_FLAG_SCSI_HOTPLUG | ATA_FLAG_RECOVERED);
 
 	/* tell wait_eh that we're done */
 	ap->flags &= ~ATA_FLAG_EH_IN_PROGRESS;
diff --git a/drivers/scsi/libata-scsi.c b/drivers/scsi/libata-scsi.c
index 3dc6188..1256399 100644
--- a/drivers/scsi/libata-scsi.c
+++ b/drivers/scsi/libata-scsi.c
@@ -2786,3 +2786,119 @@ int ata_scsi_offline_dev(struct ata_devi
 	}
 	return 0;
 }
+
+/**
+ *	ata_scsi_remove_dev - remove attached SCSI device
+ *	@dev: ATA device to remove attached SCSI device for
+ *
+ *	This function is called from ata_eh_scsi_hotplug() and
+ *	responsible for removing the SCSI device attached to @dev.
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep).
+ */
+static void ata_scsi_remove_dev(struct ata_device *dev)
+{
+	struct ata_port *ap = dev->ap;
+	struct scsi_device *sdev;
+	unsigned long flags;
+
+	/* Alas, we need to grab scan_mutex to ensure SCSI device
+	 * state doesn't change underneath us and thus
+	 * scsi_device_get() always succeeds.  The mutex locking can
+	 * be removed if there is __scsi_device_get() interface which
+	 * increments reference counts regardless of device state.
+	 */
+	mutex_lock(&ap->host->scan_mutex);
+	spin_lock_irqsave(&ap->host_set->lock, flags);
+
+	/* clearing dev->sdev is protected by host_set lock */
+	sdev = dev->sdev;
+	dev->sdev = NULL;
+
+	if (sdev) {
+		/* If user initiated unplug races with us, sdev can go
+		 * away underneath us after the host_set lock and
+		 * scan_mutex are released.  Hold onto it.
+		 */
+		if (scsi_device_get(sdev) == 0) {
+			/* The following ensures the attached sdev is
+			 * offline on return from ata_scsi_offline_dev()
+			 * regardless it wins or loses the race
+			 * against this function.
+			 */
+			scsi_device_set_state(sdev, SDEV_OFFLINE);
+		} else {
+			WARN_ON(1);
+			sdev = NULL;
+		}
+	}
+
+	spin_unlock_irqrestore(&ap->host_set->lock, flags);
+	mutex_unlock(&ap->host->scan_mutex);
+
+	if (sdev) {
+		ata_dev_printk(dev, KERN_INFO, "detaching (SCSI %s)\n",
+			       sdev->sdev_gendev.bus_id);
+
+		scsi_remove_device(sdev);
+		scsi_device_put(sdev);
+	}
+}
+
+/**
+ *	ata_scsi_hotplug - SCSI part of hotplug
+ *	@data: Pointer to ATA port to perform SCSI hotplug on
+ *
+ *	Perform SCSI part of hotplug.  It's executed from a separate
+ *	workqueue after EH completes.  This is necessary because SCSI
+ *	hot plugging requires working EH and hot unplugging is
+ *	synchronized with hot plugging with a mutex.
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep).
+ */
+void ata_scsi_hotplug(void *data)
+{
+	struct ata_port *ap = data;
+	int i;
+
+	if (ap->flags & ATA_FLAG_UNLOADING) {
+		DPRINTK("ENTER/EXIT - unloading\n");
+		return;
+	}
+
+	DPRINTK("ENTER\n");
+
+	/* unplug detached devices */
+	for (i = 0; i < ATA_MAX_DEVICES; i++) {
+		struct ata_device *dev = &ap->device[i];
+		unsigned long flags;
+
+		if (!(dev->flags & ATA_DFLAG_DETACHED))
+			continue;
+
+		spin_lock_irqsave(&ap->host_set->lock, flags);
+		dev->flags &= ~ATA_DFLAG_DETACHED;
+		spin_unlock_irqrestore(&ap->host_set->lock, flags);
+
+		ata_scsi_remove_dev(dev);
+	}
+
+	/* scan for new ones */
+	ata_scsi_scan_host(ap);
+
+	/* If we scanned while EH was in progress, scan would have
+	 * failed silently.  Requeue if there are enabled but
+	 * unattached devices.
+	 */
+	for (i = 0; i < ATA_MAX_DEVICES; i++) {
+		struct ata_device *dev = &ap->device[i];
+		if (ata_dev_enabled(dev) && !dev->sdev) {
+			queue_delayed_work(ata_aux_wq, &ap->hotplug_task, HZ);
+			break;
+		}
+	}
+
+	DPRINTK("EXIT\n");
+}
diff --git a/drivers/scsi/libata.h b/drivers/scsi/libata.h
index e38759f..0586b0c 100644
--- a/drivers/scsi/libata.h
+++ b/drivers/scsi/libata.h
@@ -76,6 +76,7 @@ extern struct scsi_transport_template at
 
 extern void ata_scsi_scan_host(struct ata_port *ap);
 extern int ata_scsi_offline_dev(struct ata_device *dev);
+extern void ata_scsi_hotplug(void *data);
 extern unsigned int ata_scsiop_inq_std(struct ata_scsi_args *args, u8 *rbuf,
 			       unsigned int buflen);
 
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 5697194..4071156 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -521,7 +521,7 @@ struct ata_port {
 	struct ata_host_set	*host_set;
 	struct device 		*dev;
 
-	struct work_struct	port_task;
+	struct work_struct	port_task, hotplug_task;
 
 	unsigned int		hsm_task_state;
 
-- 
1.3.2

Re: [PATCH 03/13] libata-hp: implement SCSI part of hotplug

[Jeff Garzik]

Tejun Heo wrote:
> diff --git a/include/linux/libata.h b/include/linux/libata.h
> index 5697194..4071156 100644
> --- a/include/linux/libata.h
> +++ b/include/linux/libata.h
> @@ -521,7 +521,7 @@ struct ata_port {
>  	struct ata_host_set	*host_set;
>  	struct device 		*dev;
>  
> -	struct work_struct	port_task;
> +	struct work_struct	port_task, hotplug_task;

nit:  break this into two lines.

ACK everything else, and ACK patches 1-2

Re: [PATCH 03/13] libata-hp: implement SCSI part of hotplug

[Tejun Heo]

Jeff Garzik wrote:
> Tejun Heo wrote:
>> diff --git a/include/linux/libata.h b/include/linux/libata.h
>> index 5697194..4071156 100644
>> --- a/include/linux/libata.h
>> +++ b/include/linux/libata.h
>> @@ -521,7 +521,7 @@ struct ata_port {
>>      struct ata_host_set    *host_set;
>>      struct device         *dev;
>>  
>> -    struct work_struct    port_task;
>> +    struct work_struct    port_task, hotplug_task;
> 
> nit:  break this into two lines.

Will do.

-- 
tejun

[PATCH 01/13] libata-hp: implement ata_eh_detach_dev()

[Tejun Heo]

Implement ata_eh_detach_dev().  This function is responsible for
detaching an ATA device and offlining the associated SCSI device
atomically so that the detached device is not accessed after ATA
detach is complete.

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

---

 drivers/scsi/libata-eh.c   |   28 ++++++++++++++++++++++++++++
 drivers/scsi/libata-scsi.c |   24 ++++++++++++++++++++++++
 drivers/scsi/libata.h      |    1 +
 3 files changed, 53 insertions(+), 0 deletions(-)

0ea035a3d1ad948096e205f08f350c03d5cea453
diff --git a/drivers/scsi/libata-eh.c b/drivers/scsi/libata-eh.c
index 8ecb842..a049bff 100644
--- a/drivers/scsi/libata-eh.c
+++ b/drivers/scsi/libata-eh.c
@@ -667,6 +667,34 @@ void ata_eh_qc_retry(struct ata_queued_c
 }
 
 /**
+ *	ata_eh_detach_dev - detach ATA device
+ *	@dev: ATA device to detach
+ *
+ *	Detach @dev.
+ *
+ *	LOCKING:
+ *	None.
+ */
+static void ata_eh_detach_dev(struct ata_device *dev)
+{
+	struct ata_port *ap = dev->ap;
+	unsigned long flags;
+
+	ata_dev_disable(dev);
+
+	spin_lock_irqsave(&ap->host_set->lock, flags);
+
+	dev->flags &= ~ATA_DFLAG_DETACH;
+
+	if (ata_scsi_offline_dev(dev)) {
+		dev->flags |= ATA_DFLAG_DETACHED;
+		ap->flags |= ATA_FLAG_SCSI_HOTPLUG;
+	}
+
+	spin_unlock_irqrestore(&ap->host_set->lock, flags);
+}
+
+/**
  *	ata_eh_about_to_do - about to perform eh_action
  *	@ap: target ATA port
  *	@action: action about to be performed
diff --git a/drivers/scsi/libata-scsi.c b/drivers/scsi/libata-scsi.c
index da9689b..3dc6188 100644
--- a/drivers/scsi/libata-scsi.c
+++ b/drivers/scsi/libata-scsi.c
@@ -2762,3 +2762,27 @@ void ata_scsi_scan_host(struct ata_port 
 		}
 	}
 }
+
+/**
+ *	ata_scsi_offline_dev - offline attached SCSI device
+ *	@dev: ATA device to offline attached SCSI device for
+ *
+ *	This function is called from ata_eh_hotplug() and responsible
+ *	for taking the SCSI device attached to @dev offline.  This
+ *	function is called with host_set lock which protects dev->sdev
+ *	against clearing.
+ *
+ *	LOCKING:
+ *	spin_lock_irqsave(host_set lock)
+ *
+ *	RETURNS:
+ *	1 if attached SCSI device exists, 0 otherwise.
+ */
+int ata_scsi_offline_dev(struct ata_device *dev)
+{
+	if (dev->sdev) {
+		scsi_device_set_state(dev->sdev, SDEV_OFFLINE);
+		return 1;
+	}
+	return 0;
+}
diff --git a/drivers/scsi/libata.h b/drivers/scsi/libata.h
index 2d704be..e38759f 100644
--- a/drivers/scsi/libata.h
+++ b/drivers/scsi/libata.h
@@ -75,6 +75,7 @@ extern int ata_cmd_ioctl(struct scsi_dev
 extern struct scsi_transport_template ata_scsi_transport_template;
 
 extern void ata_scsi_scan_host(struct ata_port *ap);
+extern int ata_scsi_offline_dev(struct ata_device *dev);
 extern unsigned int ata_scsiop_inq_std(struct ata_scsi_args *args, u8 *rbuf,
 			       unsigned int buflen);
 
-- 
1.3.2

[PATCH 02/13] libata-hp: implement hotplug

[Tejun Heo]

Implement ATA part of hotplug.  To avoid probing broken devices over
and over again, disabled devices are not automatically detached.  They
are detached only if probing is requested for the device or the
associated port is offline.  Also, to avoid infinite probing loop,
Each device is probed only once per EH run.

As SATA PHY status is fragile, devices are detached only after it has
used up its recovery chances unless explicitly requested by LLDD or
user (LLDD may request direct detach if, for example, it supports cold
presence detection).

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

---

 drivers/scsi/libata-eh.c |  123 ++++++++++++++++++++++++++++++++++++++--------
 include/linux/libata.h   |   13 +++++
 2 files changed, 115 insertions(+), 21 deletions(-)

084fe639b81c4d418a2cf714acb0475e3713cb73
diff --git a/drivers/scsi/libata-eh.c b/drivers/scsi/libata-eh.c
index a049bff..b53e2e7 100644
--- a/drivers/scsi/libata-eh.c
+++ b/drivers/scsi/libata-eh.c
@@ -932,10 +932,8 @@ static void ata_eh_analyze_serror(struct
 		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;
-	}
+	if (serror & (SERR_PHYRDY_CHG | SERR_DEV_XCHG))
+		ata_ehi_hotplugged(&ehc->i);
 
 	ehc->i.err_mask |= err_mask;
 	ehc->i.action |= action;
@@ -1487,11 +1485,12 @@ static int ata_eh_reset(struct ata_port 
 	return rc;
 }
 
-static int ata_eh_revalidate(struct ata_port *ap,
-			     struct ata_device **r_failed_dev)
+static int ata_eh_revalidate_and_attach(struct ata_port *ap,
+					struct ata_device **r_failed_dev)
 {
 	struct ata_eh_context *ehc = &ap->eh_context;
 	struct ata_device *dev;
+	unsigned long flags;
 	int i, rc = 0;
 
 	DPRINTK("ENTER\n");
@@ -1513,6 +1512,23 @@ static int ata_eh_revalidate(struct ata_
 				break;
 
 			ehc->i.action &= ~ATA_EH_REVALIDATE;
+		} else if (dev->class == ATA_DEV_UNKNOWN &&
+			   ehc->tries[dev->devno] &&
+			   ata_class_enabled(ehc->classes[dev->devno])) {
+			dev->class = ehc->classes[dev->devno];
+
+			rc = ata_dev_read_id(dev, &dev->class, 1, dev->id);
+			if (rc == 0)
+				rc = ata_dev_configure(dev, 1);
+
+			if (rc) {
+				dev->class = ATA_DEV_UNKNOWN;
+				break;
+			}
+
+			spin_lock_irqsave(&ap->host_set->lock, flags);
+			ap->flags |= ATA_FLAG_SCSI_HOTPLUG;
+			spin_unlock_irqrestore(&ap->host_set->lock, flags);
 		}
 	}
 
@@ -1533,6 +1549,36 @@ static int ata_port_nr_enabled(struct at
 	return cnt;
 }
 
+static int ata_port_nr_vacant(struct ata_port *ap)
+{
+	int i, cnt = 0;
+
+	for (i = 0; i < ATA_MAX_DEVICES; i++)
+		if (ap->device[i].class == ATA_DEV_UNKNOWN)
+			cnt++;
+	return cnt;
+}
+
+static int ata_eh_skip_recovery(struct ata_port *ap)
+{
+	struct ata_eh_context *ehc = &ap->eh_context;
+	int i;
+
+	if (ap->flags & ATA_FLAG_FROZEN || ata_port_nr_enabled(ap))
+		return 0;
+
+	/* skip if class codes for all vacant slots are ATA_DEV_NONE */
+	for (i = 0; i < ATA_MAX_DEVICES; i++) {
+		struct ata_device *dev = &ap->device[i];
+
+		if (dev->class == ATA_DEV_UNKNOWN &&
+		    ehc->classes[dev->devno] != ATA_DEV_NONE)
+			return 0;
+	}
+
+	return 1;
+}
+
 /**
  *	ata_eh_recover - recover host port after error
  *	@ap: host port to recover
@@ -1543,9 +1589,10 @@ static int ata_port_nr_enabled(struct at
  *
  *	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.
+ *	recover the port and hotplug requests are recorded in
+ *	eh_context.  This function executes all the operations with
+ *	appropriate retrials and fallbacks to resurrect failed
+ *	devices, detach goners and greet newcomers.
  *
  *	LOCKING:
  *	Kernel thread context (may sleep).
@@ -1568,6 +1615,19 @@ static int ata_eh_recover(struct ata_por
 		dev = &ap->device[i];
 
 		ehc->tries[dev->devno] = ATA_EH_DEV_TRIES;
+
+		/* process hotplug request */
+		if (dev->flags & ATA_DFLAG_DETACH)
+			ata_eh_detach_dev(dev);
+
+		if (!ata_dev_enabled(dev) &&
+		    ((ehc->i.probe_mask & (1 << dev->devno)) &&
+		     !(ehc->did_probe_mask & (1 << dev->devno)))) {
+			ata_eh_detach_dev(dev);
+			ata_dev_init(dev);
+			ehc->did_probe_mask |= (1 << dev->devno);
+			ehc->i.action |= ATA_EH_SOFTRESET;
+		}
 	}
 
  retry:
@@ -1575,15 +1635,18 @@ static int ata_eh_recover(struct ata_por
 	rc = 0;
 
 	/* skip EH if possible. */
-	if (!ata_port_nr_enabled(ap) && !(ap->flags & ATA_FLAG_FROZEN))
+	if (ata_eh_skip_recovery(ap))
 		ehc->i.action = 0;
 
+	for (i = 0; i < ATA_MAX_DEVICES; i++)
+		ehc->classes[i] = ATA_DEV_UNKNOWN;
+
 	/* reset */
 	if (ehc->i.action & ATA_EH_RESET_MASK) {
 		ata_eh_freeze_port(ap);
 
-		rc = ata_eh_reset(ap, 0, prereset, softreset, hardreset,
-				  postreset);
+		rc = ata_eh_reset(ap, ata_port_nr_vacant(ap), prereset,
+				  softreset, hardreset, postreset);
 		if (rc) {
 			ata_port_printk(ap, KERN_ERR,
 					"reset failed, giving up\n");
@@ -1593,8 +1656,8 @@ static int ata_eh_recover(struct ata_por
 		ata_eh_thaw_port(ap);
 	}
 
-	/* revalidate existing devices */
-	rc = ata_eh_revalidate(ap, &dev);
+	/* revalidate existing devices and attach new ones */
+	rc = ata_eh_revalidate_and_attach(ap, &dev);
 	if (rc)
 		goto dev_fail;
 
@@ -1612,6 +1675,8 @@ static int ata_eh_recover(struct ata_por
  dev_fail:
 	switch (rc) {
 	case -ENODEV:
+		/* device missing, schedule probing */
+		ehc->i.probe_mask |= (1 << dev->devno);
 	case -EINVAL:
 		ehc->tries[dev->devno] = 0;
 		break;
@@ -1624,15 +1689,31 @@ static int ata_eh_recover(struct ata_por
 			ehc->tries[dev->devno] = 0;
 	}
 
-	/* disable device if it has used up all its chances */
-	if (ata_dev_enabled(dev) && !ehc->tries[dev->devno])
+	if (ata_dev_enabled(dev) && !ehc->tries[dev->devno]) {
+		/* disable device if it has used up all its chances */
 		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;
+		/* detach if offline */
+		if (ata_port_offline(ap))
+			ata_eh_detach_dev(dev);
+
+		/* probe if requested */
+		if ((ehc->i.probe_mask & (1 << dev->devno)) &&
+		    !(ehc->did_probe_mask & (1 << dev->devno))) {
+			ata_eh_detach_dev(dev);
+			ata_dev_init(dev);
+
+			ehc->tries[dev->devno] = ATA_EH_DEV_TRIES;
+			ehc->did_probe_mask |= (1 << dev->devno);
+			ehc->i.action |= ATA_EH_SOFTRESET;
+		}
+	} else {
+		/* soft didn't work?  be haaaaard */
+		if (ehc->i.flags & ATA_EHI_DID_RESET)
+			ehc->i.action |= ATA_EH_HARDRESET;
+		else
+			ehc->i.action |= ATA_EH_SOFTRESET;
+	}
 
 	if (ata_port_nr_enabled(ap)) {
 		ata_port_printk(ap, KERN_WARNING, "failed to recover some "
diff --git a/include/linux/libata.h b/include/linux/libata.h
index a1ceb5b..5697194 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -824,6 +824,19 @@ #define ata_ehi_clear_desc(ehi) do { \
 	(ehi)->desc_len = 0; \
 } while (0)
 
+static inline void ata_ehi_hotplugged(struct ata_eh_info *ehi)
+{
+	if (ehi->flags & ATA_EHI_HOTPLUGGED)
+		return;
+
+	ehi->flags |= ATA_EHI_HOTPLUGGED;
+	ehi->hotplug_timestamp = jiffies;
+
+	ehi->err_mask |= AC_ERR_ATA_BUS;
+	ehi->action |= ATA_EH_SOFTRESET;
+	ehi->probe_mask |= (1 << ATA_MAX_DEVICES) - 1;
+}
+
 /*
  * qc helpers
  */
-- 
1.3.2

[PATCH 09/13] sata_sil: convert to new probing mechanism and add hotplug support

[Tejun Heo]

Convert to new probing mechanism and add hotplug support by enabling
SATA IRQ for SError.N, marking ehi for hotplug and scheduling EH on
SATA IRQs.

Sil3112/3512/3114 family of controllers use COMRESET as TF clearing
point and can reliably wait for D2H FIS after COMRESET whether the FIS
is the first D2H FIS after POR or in response to the COMRESET.  Thus,
setting ATA_FLAG_HRST_TO_RESUME is enough for device detection after
hotplug.

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

---

 drivers/scsi/sata_sil.c |   21 +++++++++++++--------
 1 files changed, 13 insertions(+), 8 deletions(-)

e573890b00426189e1e223967a2c46fb758bf06e
diff --git a/drivers/scsi/sata_sil.c b/drivers/scsi/sata_sil.c
index 7d43cd3..0898cbe 100644
--- a/drivers/scsi/sata_sil.c
+++ b/drivers/scsi/sata_sil.c
@@ -56,7 +56,7 @@ enum {
 	SIL_FLAG_MOD15WRITE	= (1 << 30),
 
 	SIL_DFL_HOST_FLAGS	= ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY |
-				  ATA_FLAG_MMIO,
+				  ATA_FLAG_MMIO | ATA_FLAG_HRST_TO_RESUME,
 
 	/*
 	 * Controller IDs
@@ -186,7 +186,6 @@ static const struct ata_port_operations 
 	.check_status		= ata_check_status,
 	.exec_command		= ata_exec_command,
 	.dev_select		= ata_std_dev_select,
-	.probe_reset		= ata_std_probe_reset,
 	.post_set_mode		= sil_post_set_mode,
 	.bmdma_setup            = ata_bmdma_setup,
 	.bmdma_start            = ata_bmdma_start,
@@ -344,6 +343,11 @@ static void sil_host_intr(struct ata_por
 	struct ata_queued_cmd *qc = ata_qc_from_tag(ap, ap->active_tag);
 	u8 status;
 
+	if (unlikely(bmdma2 & SIL_DMA_SATA_IRQ)) {
+		ata_ehi_hotplugged(&ap->eh_info);
+		goto freeze;
+	}
+
 	if (unlikely(!qc || qc->tf.ctl & ATA_NIEN))
 		goto freeze;
 
@@ -415,7 +419,7 @@ static irqreturn_t sil_interrupt(int irq
 		if (unlikely(!ap || ap->flags & ATA_FLAG_DISABLED))
 			continue;
 
-		if (!(bmdma2 & SIL_DMA_COMPLETE))
+		if (!(bmdma2 & (SIL_DMA_COMPLETE | SIL_DMA_SATA_IRQ)))
 			continue;
 
 		sil_host_intr(ap, bmdma2);
@@ -432,6 +436,9 @@ static void sil_freeze(struct ata_port *
 	void __iomem *mmio_base = ap->host_set->mmio_base;
 	u32 tmp;
 
+	/* global IRQ mask doesn't block SATA IRQ, turn off explicitly */
+	writel(0, mmio_base + sil_port[ap->port_no].sien);
+
 	/* plug IRQ */
 	tmp = readl(mmio_base + SIL_SYSCFG);
 	tmp |= SIL_MASK_IDE0_INT << ap->port_no;
@@ -448,6 +455,9 @@ static void sil_thaw(struct ata_port *ap
 	ata_chk_status(ap);
 	ata_bmdma_irq_clear(ap);
 
+	/* turn on SATA IRQ */
+	writel(SIL_SIEN_N, mmio_base + sil_port[ap->port_no].sien);
+
 	/* turn on IRQ */
 	tmp = readl(mmio_base + SIL_SYSCFG);
 	tmp &= ~(SIL_MASK_IDE0_INT << ap->port_no);
@@ -621,11 +631,6 @@ static int sil_init_one (struct pci_dev 
 			       mmio_base + sil_port[2].bmdma);
 	}
 
-	/* mask all SATA phy-related interrupts */
-	/* TODO: unmask bit 6 (SError N bit) for hotplug */
-	for (i = 0; i < probe_ent->n_ports; i++)
-		writel(0, mmio_base + sil_port[i].sien);
-
 	pci_set_master(pdev);
 
 	/* FIXME: check ata_device_add return value */
-- 
1.3.2

[PATCH 10/13] ahci: convert to new probing mechanism and add hotplug support

[Tejun Heo]

Convert to new probing mechanism and add hotplug support by enabling
PORT_IRQ_PHYRDY, marking ehi for hotplug and scheduling EH on
CONNECT/PHYRDY interrupts.

Unfortunately, ahci cannot reliably wait for the first D2H FIS after
hotplug.  It sometimes succeeds but times out more often than not, so
ATA_FLAG_SKIP_D2H_BSY is used.

This patch also fixes ahci_hardreset() such that D2H Register FIS RX
area is cleared before issuing COMRESET.  Without this,
ata_busy_sleep() after COMRESET might prematually finish if the
previous TF contains DRDY && !BSY.

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

---

 drivers/scsi/ahci.c |   47 +++++++++++++++++++++++++++--------------------
 1 files changed, 27 insertions(+), 20 deletions(-)

4296971dd36e2c2deae0826305f591480223af88
diff --git a/drivers/scsi/ahci.c b/drivers/scsi/ahci.c
index 60f455b..e261b37 100644
--- a/drivers/scsi/ahci.c
+++ b/drivers/scsi/ahci.c
@@ -136,6 +136,7 @@ enum {
 	PORT_IRQ_FREEZE		= PORT_IRQ_HBUS_ERR |
 				  PORT_IRQ_IF_ERR |
 				  PORT_IRQ_CONNECT |
+				  PORT_IRQ_PHYRDY |
 				  PORT_IRQ_UNK_FIS,
 	PORT_IRQ_ERROR		= PORT_IRQ_FREEZE |
 				  PORT_IRQ_TF_ERR |
@@ -200,7 +201,6 @@ static void ahci_scr_write (struct ata_p
 static int ahci_init_one (struct pci_dev *pdev, const struct pci_device_id *ent);
 static unsigned int ahci_qc_issue(struct ata_queued_cmd *qc);
 static irqreturn_t ahci_interrupt (int irq, void *dev_instance, struct pt_regs *regs);
-static int ahci_probe_reset(struct ata_port *ap, unsigned int *classes);
 static void ahci_irq_clear(struct ata_port *ap);
 static int ahci_port_start(struct ata_port *ap);
 static void ahci_port_stop(struct ata_port *ap);
@@ -241,8 +241,6 @@ static const struct ata_port_operations 
 
 	.tf_read		= ahci_tf_read,
 
-	.probe_reset		= ahci_probe_reset,
-
 	.qc_prep		= ahci_qc_prep,
 	.qc_issue		= ahci_qc_issue,
 
@@ -267,7 +265,8 @@ static const struct ata_port_info ahci_p
 	{
 		.sht		= &ahci_sht,
 		.host_flags	= ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY |
-				  ATA_FLAG_MMIO | ATA_FLAG_PIO_DMA,
+				  ATA_FLAG_MMIO | ATA_FLAG_PIO_DMA |
+				  ATA_FLAG_SKIP_D2H_BSY,
 		.pio_mask	= 0x1f, /* pio0-4 */
 		.udma_mask	= 0x7f, /* udma0-6 ; FIXME */
 		.port_ops	= &ahci_ops,
@@ -277,6 +276,7 @@ static const struct ata_port_info ahci_p
 		.sht		= &ahci_sht,
 		.host_flags	= ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY |
 				  ATA_FLAG_MMIO | ATA_FLAG_PIO_DMA |
+				  ATA_FLAG_SKIP_D2H_BSY |
 				  AHCI_FLAG_RESET_NEEDS_CLO,
 		.pio_mask	= 0x1f, /* pio0-4 */
 		.udma_mask	= 0x7f, /* udma0-6 ; FIXME */
@@ -569,6 +569,17 @@ static int ahci_clo(struct ata_port *ap)
 	return 0;
 }
 
+static int ahci_prereset(struct ata_port *ap)
+{
+	if ((ap->flags & AHCI_FLAG_RESET_NEEDS_CLO) &&
+	    (ata_busy_wait(ap, ATA_BUSY, 1000) & ATA_BUSY)) {
+		/* ATA_BUSY hasn't cleared, so send a CLO */
+		ahci_clo(ap);
+	}
+
+	return ata_std_prereset(ap);
+}
+
 static int ahci_softreset(struct ata_port *ap, unsigned int *class)
 {
 	struct ahci_port_priv *pp = ap->private_data;
@@ -678,12 +689,22 @@ static int ahci_softreset(struct ata_por
 
 static int ahci_hardreset(struct ata_port *ap, unsigned int *class)
 {
+	struct ahci_port_priv *pp = ap->private_data;
+	u8 *d2h_fis = pp->rx_fis + RX_FIS_D2H_REG;
+	struct ata_taskfile tf;
 	int rc;
 
 	DPRINTK("ENTER\n");
 
 	ahci_stop_engine(ap);
+
+	/* clear D2H reception area to properly wait for D2H FIS */
+	ata_tf_init(ap->device, &tf);
+	tf.command = 0xff;
+	ata_tf_to_fis(&tf, d2h_fis, 0);
+
 	rc = sata_std_hardreset(ap, class);
+
 	ahci_start_engine(ap);
 
 	if (rc == 0 && ata_port_online(ap))
@@ -714,19 +735,6 @@ static void ahci_postreset(struct ata_po
 	}
 }
 
-static int ahci_probe_reset(struct ata_port *ap, unsigned int *classes)
-{
-	if ((ap->flags & AHCI_FLAG_RESET_NEEDS_CLO) &&
-	    (ata_busy_wait(ap, ATA_BUSY, 1000) & ATA_BUSY)) {
-		/* ATA_BUSY hasn't cleared, so send a CLO */
-		ahci_clo(ap);
-	}
-
-	return ata_drive_probe_reset(ap, ata_std_probeinit,
-				     ahci_softreset, ahci_hardreset,
-				     ahci_postreset, classes);
-}
-
 static u8 ahci_check_status(struct ata_port *ap)
 {
 	void __iomem *mmio = (void __iomem *) ap->ioaddr.cmd_addr;
@@ -839,8 +847,7 @@ static void ahci_error_intr(struct ata_p
 	}
 
 	if (irq_stat & (PORT_IRQ_CONNECT | PORT_IRQ_PHYRDY)) {
-		err_mask |= AC_ERR_ATA_BUS;
-		action |= ATA_EH_SOFTRESET;
+		ata_ehi_hotplugged(ehi);
 		ata_ehi_push_desc(ehi, ", %s", irq_stat & PORT_IRQ_CONNECT ?
 			"connection status changed" : "PHY RDY changed");
 	}
@@ -1027,7 +1034,7 @@ static void ahci_error_handler(struct at
 	}
 
 	/* perform recovery */
-	ata_do_eh(ap, ata_std_prereset, ahci_softreset, ahci_hardreset,
+	ata_do_eh(ap, ahci_prereset, ahci_softreset, ahci_hardreset,
 		  ahci_postreset);
 }
 
-- 
1.3.2

[PATCH 07/13] libata-hp: update unload-unplug

[Tejun Heo]

Update unload unplug - driver unloading / PCI removal.  This is done
by ata_port_detach() which short-circuits EH, disables all devices and
freezes the port.  With this patch, EH and unloading/unplugging are
properly synchronized.

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

---

 drivers/scsi/ahci.c        |   10 ++-----
 drivers/scsi/libata-core.c |   67 ++++++++++++++++++++++++++++++++++++++++----
 drivers/scsi/libata-eh.c   |    8 ++++-
 include/linux/libata.h     |    1 +
 4 files changed, 71 insertions(+), 15 deletions(-)

720ba12620ee09dce269adf4ad50958adac7bb54
diff --git a/drivers/scsi/ahci.c b/drivers/scsi/ahci.c
index afb3805..60f455b 100644
--- a/drivers/scsi/ahci.c
+++ b/drivers/scsi/ahci.c
@@ -1389,21 +1389,17 @@ static void ahci_remove_one (struct pci_
 	struct device *dev = pci_dev_to_dev(pdev);
 	struct ata_host_set *host_set = dev_get_drvdata(dev);
 	struct ahci_host_priv *hpriv = host_set->private_data;
-	struct ata_port *ap;
 	unsigned int i;
 	int have_msi;
 
-	for (i = 0; i < host_set->n_ports; i++) {
-		ap = host_set->ports[i];
-
-		scsi_remove_host(ap->host);
-	}
+	for (i = 0; i < host_set->n_ports; i++)
+		ata_port_detach(host_set->ports[i]);
 
 	have_msi = hpriv->flags & AHCI_FLAG_MSI;
 	free_irq(host_set->irq, host_set);
 
 	for (i = 0; i < host_set->n_ports; i++) {
-		ap = host_set->ports[i];
+		struct ata_port *ap = host_set->ports[i];
 
 		ata_scsi_release(ap->host);
 		scsi_host_put(ap->host);
diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index a42877e..01f2c59 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -5610,6 +5610,63 @@ err_free_ret:
 }
 
 /**
+ *	ata_port_detach - Detach ATA port in prepration of device removal
+ *	@ap: ATA port to be detached
+ *
+ *	Detach all ATA devices and the associated SCSI devices of @ap;
+ *	then, remove the associated SCSI host.  @ap is guaranteed to
+ *	be quiescent on return from this function.
+ *
+ *	LOCKING:
+ *	Kernel thread context (may sleep).
+ */
+void ata_port_detach(struct ata_port *ap)
+{
+	unsigned long flags;
+	int i;
+
+	if (!ap->ops->error_handler)
+		return;
+
+	/* tell EH we're leaving & flush EH */
+	spin_lock_irqsave(&ap->host_set->lock, flags);
+	ap->flags |= ATA_FLAG_UNLOADING;
+	spin_unlock_irqrestore(&ap->host_set->lock, flags);
+
+	ata_port_wait_eh(ap);
+
+	/* EH is now guaranteed to see UNLOADING, so no new device
+	 * will be attached.  Disable all existing devices.
+	 */
+	spin_lock_irqsave(&ap->host_set->lock, flags);
+
+	for (i = 0; i < ATA_MAX_DEVICES; i++)
+		ata_dev_disable(&ap->device[i]);
+
+	spin_unlock_irqrestore(&ap->host_set->lock, flags);
+
+	/* Final freeze & EH.  All in-flight commands are aborted.  EH
+	 * will be skipped and retrials will be terminated with bad
+	 * target.
+	 */
+	spin_lock_irqsave(&ap->host_set->lock, flags);
+	ata_port_freeze(ap);	/* won't be thawed */
+	spin_unlock_irqrestore(&ap->host_set->lock, flags);
+
+	ata_port_wait_eh(ap);
+
+	/* Flush hotplug task.  The sequence is similar to
+	 * ata_port_flush_task().
+	 */
+	flush_workqueue(ata_aux_wq);
+	cancel_delayed_work(&ap->hotplug_task);
+	flush_workqueue(ata_aux_wq);
+
+	/* remove the associated SCSI host */
+	scsi_remove_host(ap->host);
+}
+
+/**
  *	ata_host_set_remove - PCI layer callback for device removal
  *	@host_set: ATA host set that was removed
  *
@@ -5622,18 +5679,15 @@ err_free_ret:
 
 void ata_host_set_remove(struct ata_host_set *host_set)
 {
-	struct ata_port *ap;
 	unsigned int i;
 
-	for (i = 0; i < host_set->n_ports; i++) {
-		ap = host_set->ports[i];
-		scsi_remove_host(ap->host);
-	}
+	for (i = 0; i < host_set->n_ports; i++)
+		ata_port_detach(host_set->ports[i]);
 
 	free_irq(host_set->irq, host_set);
 
 	for (i = 0; i < host_set->n_ports; i++) {
-		ap = host_set->ports[i];
+		struct ata_port *ap = host_set->ports[i];
 
 		ata_scsi_release(ap->host);
 
@@ -5901,6 +5955,7 @@ EXPORT_SYMBOL_GPL(sata_deb_timing_before
 EXPORT_SYMBOL_GPL(ata_std_bios_param);
 EXPORT_SYMBOL_GPL(ata_std_ports);
 EXPORT_SYMBOL_GPL(ata_device_add);
+EXPORT_SYMBOL_GPL(ata_port_detach);
 EXPORT_SYMBOL_GPL(ata_host_set_remove);
 EXPORT_SYMBOL_GPL(ata_sg_init);
 EXPORT_SYMBOL_GPL(ata_sg_init_one);
diff --git a/drivers/scsi/libata-eh.c b/drivers/scsi/libata-eh.c
index 70c132b..30a83a5 100644
--- a/drivers/scsi/libata-eh.c
+++ b/drivers/scsi/libata-eh.c
@@ -46,6 +46,7 @@ #include <linux/libata.h>
 #include "libata.h"
 
 static void __ata_port_freeze(struct ata_port *ap);
+static void ata_eh_finish(struct ata_port *ap);
 
 static void ata_ering_record(struct ata_ering *ering, int is_io,
 			     unsigned int err_mask)
@@ -242,8 +243,11 @@ void ata_scsi_error(struct Scsi_Host *ho
 
 		spin_unlock_irqrestore(hs_lock, flags);
 
-		/* invoke EH */
-		ap->ops->error_handler(ap);
+		/* invoke EH.  if unloading, just finish failed qcs */
+		if (!(ap->flags & ATA_FLAG_UNLOADING))
+			ap->ops->error_handler(ap);
+		else
+			ata_eh_finish(ap);
 
 		/* Exception might have happend after ->error_handler
 		 * recovered the port but before this point.  Repeat
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 74786c3..f11ba27 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -649,6 +649,7 @@ extern int ata_pci_device_resume(struct 
 extern int ata_pci_clear_simplex(struct pci_dev *pdev);
 #endif /* CONFIG_PCI */
 extern int ata_device_add(const struct ata_probe_ent *ent);
+extern void ata_port_detach(struct ata_port *ap);
 extern void ata_host_set_remove(struct ata_host_set *host_set);
 extern int ata_scsi_detect(struct scsi_host_template *sht);
 extern int ata_scsi_ioctl(struct scsi_device *dev, int cmd, void __user *arg);
-- 
1.3.2

[PATCH 05/13] libata-hp: hook warmplug

[Tejun Heo]

Hook transportt->user_scan() and hostt->slave_destroy().

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

---

 drivers/scsi/ahci.c         |    1 +
 drivers/scsi/ata_piix.c     |    1 +
 drivers/scsi/libata-scsi.c  |    1 +
 drivers/scsi/pdc_adma.c     |    1 +
 drivers/scsi/sata_mv.c      |    1 +
 drivers/scsi/sata_nv.c      |    1 +
 drivers/scsi/sata_promise.c |    1 +
 drivers/scsi/sata_qstor.c   |    1 +
 drivers/scsi/sata_sil.c     |    1 +
 drivers/scsi/sata_sil24.c   |    1 +
 drivers/scsi/sata_sis.c     |    1 +
 drivers/scsi/sata_svw.c     |    1 +
 drivers/scsi/sata_sx4.c     |    1 +
 drivers/scsi/sata_uli.c     |    1 +
 drivers/scsi/sata_via.c     |    1 +
 drivers/scsi/sata_vsc.c     |    1 +
 16 files changed, 16 insertions(+), 0 deletions(-)

ccf68c3405fca11386004674377d951b9b18e756
diff --git a/drivers/scsi/ahci.c b/drivers/scsi/ahci.c
index 8493b02..afb3805 100644
--- a/drivers/scsi/ahci.c
+++ b/drivers/scsi/ahci.c
@@ -228,6 +228,7 @@ static struct scsi_host_template ahci_sh
 	.proc_name		= DRV_NAME,
 	.dma_boundary		= AHCI_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
+	.slave_destroy		= ata_scsi_slave_destroy,
 	.bios_param		= ata_std_bios_param,
 };
 
diff --git a/drivers/scsi/ata_piix.c b/drivers/scsi/ata_piix.c
index ad41dfd..54c2e52 100644
--- a/drivers/scsi/ata_piix.c
+++ b/drivers/scsi/ata_piix.c
@@ -219,6 +219,7 @@ static struct scsi_host_template piix_sh
 	.proc_name		= DRV_NAME,
 	.dma_boundary		= ATA_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
+	.slave_destroy		= ata_scsi_slave_destroy,
 	.bios_param		= ata_std_bios_param,
 	.resume			= ata_scsi_device_resume,
 	.suspend		= ata_scsi_device_suspend,
diff --git a/drivers/scsi/libata-scsi.c b/drivers/scsi/libata-scsi.c
index 7c1ac58..5f90d8e 100644
--- a/drivers/scsi/libata-scsi.c
+++ b/drivers/scsi/libata-scsi.c
@@ -107,6 +107,7 @@ static const u8 def_control_mpage[CONTRO
 struct scsi_transport_template ata_scsi_transport_template = {
 	.eh_strategy_handler	= ata_scsi_error,
 	.eh_timed_out		= ata_scsi_timed_out,
+	.user_scan		= ata_scsi_user_scan,
 };
 
 
diff --git a/drivers/scsi/pdc_adma.c b/drivers/scsi/pdc_adma.c
index a341fa8..eb910e4 100644
--- a/drivers/scsi/pdc_adma.c
+++ b/drivers/scsi/pdc_adma.c
@@ -152,6 +152,7 @@ static struct scsi_host_template adma_at
 	.proc_name		= DRV_NAME,
 	.dma_boundary		= ADMA_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
+	.slave_destroy		= ata_scsi_slave_destroy,
 	.bios_param		= ata_std_bios_param,
 };
 
diff --git a/drivers/scsi/sata_mv.c b/drivers/scsi/sata_mv.c
index 624983c..634bab1 100644
--- a/drivers/scsi/sata_mv.c
+++ b/drivers/scsi/sata_mv.c
@@ -390,6 +390,7 @@ static struct scsi_host_template mv_sht 
 	.proc_name		= DRV_NAME,
 	.dma_boundary		= MV_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
+	.slave_destroy		= ata_scsi_slave_destroy,
 	.bios_param		= ata_std_bios_param,
 };
 
diff --git a/drivers/scsi/sata_nv.c b/drivers/scsi/sata_nv.c
index d93513e..9055124 100644
--- a/drivers/scsi/sata_nv.c
+++ b/drivers/scsi/sata_nv.c
@@ -216,6 +216,7 @@ static struct scsi_host_template nv_sht 
 	.proc_name		= DRV_NAME,
 	.dma_boundary		= ATA_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
+	.slave_destroy		= ata_scsi_slave_destroy,
 	.bios_param		= ata_std_bios_param,
 };
 
diff --git a/drivers/scsi/sata_promise.c b/drivers/scsi/sata_promise.c
index 0111159..b2b6ed5 100644
--- a/drivers/scsi/sata_promise.c
+++ b/drivers/scsi/sata_promise.c
@@ -121,6 +121,7 @@ static struct scsi_host_template pdc_ata
 	.proc_name		= DRV_NAME,
 	.dma_boundary		= ATA_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
+	.slave_destroy		= ata_scsi_slave_destroy,
 	.bios_param		= ata_std_bios_param,
 };
 
diff --git a/drivers/scsi/sata_qstor.c b/drivers/scsi/sata_qstor.c
index 68737ca..98ddc25 100644
--- a/drivers/scsi/sata_qstor.c
+++ b/drivers/scsi/sata_qstor.c
@@ -142,6 +142,7 @@ static struct scsi_host_template qs_ata_
 	.proc_name		= DRV_NAME,
 	.dma_boundary		= QS_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
+	.slave_destroy		= ata_scsi_slave_destroy,
 	.bios_param		= ata_std_bios_param,
 };
 
diff --git a/drivers/scsi/sata_sil.c b/drivers/scsi/sata_sil.c
index 03c1d1b..7d43cd3 100644
--- a/drivers/scsi/sata_sil.c
+++ b/drivers/scsi/sata_sil.c
@@ -174,6 +174,7 @@ static struct scsi_host_template sil_sht
 	.proc_name		= DRV_NAME,
 	.dma_boundary		= ATA_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
+	.slave_destroy		= ata_scsi_slave_destroy,
 	.bios_param		= ata_std_bios_param,
 };
 
diff --git a/drivers/scsi/sata_sil24.c b/drivers/scsi/sata_sil24.c
index 4a83090..d4ca6d6 100644
--- a/drivers/scsi/sata_sil24.c
+++ b/drivers/scsi/sata_sil24.c
@@ -370,6 +370,7 @@ static struct scsi_host_template sil24_s
 	.proc_name		= DRV_NAME,
 	.dma_boundary		= ATA_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
+	.slave_destroy		= ata_scsi_slave_destroy,
 	.bios_param		= ata_std_bios_param,
 };
 
diff --git a/drivers/scsi/sata_sis.c b/drivers/scsi/sata_sis.c
index 82a07bf..a07e6e5 100644
--- a/drivers/scsi/sata_sis.c
+++ b/drivers/scsi/sata_sis.c
@@ -96,6 +96,7 @@ static struct scsi_host_template sis_sht
 	.proc_name		= DRV_NAME,
 	.dma_boundary		= ATA_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
+	.slave_destroy		= ata_scsi_slave_destroy,
 	.bios_param		= ata_std_bios_param,
 };
 
diff --git a/drivers/scsi/sata_svw.c b/drivers/scsi/sata_svw.c
index 7a4703b..d9b5168 100644
--- a/drivers/scsi/sata_svw.c
+++ b/drivers/scsi/sata_svw.c
@@ -299,6 +299,7 @@ static struct scsi_host_template k2_sata
 	.proc_name		= DRV_NAME,
 	.dma_boundary		= ATA_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
+	.slave_destroy		= ata_scsi_slave_destroy,
 #ifdef CONFIG_PPC_OF
 	.proc_info		= k2_sata_proc_info,
 #endif
diff --git a/drivers/scsi/sata_sx4.c b/drivers/scsi/sata_sx4.c
index c4db6bf..7f86441 100644
--- a/drivers/scsi/sata_sx4.c
+++ b/drivers/scsi/sata_sx4.c
@@ -191,6 +191,7 @@ static struct scsi_host_template pdc_sat
 	.proc_name		= DRV_NAME,
 	.dma_boundary		= ATA_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
+	.slave_destroy		= ata_scsi_slave_destroy,
 	.bios_param		= ata_std_bios_param,
 };
 
diff --git a/drivers/scsi/sata_uli.c b/drivers/scsi/sata_uli.c
index 7fae3e0..e69ba22 100644
--- a/drivers/scsi/sata_uli.c
+++ b/drivers/scsi/sata_uli.c
@@ -90,6 +90,7 @@ static struct scsi_host_template uli_sht
 	.proc_name		= DRV_NAME,
 	.dma_boundary		= ATA_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
+	.slave_destroy		= ata_scsi_slave_destroy,
 	.bios_param		= ata_std_bios_param,
 };
 
diff --git a/drivers/scsi/sata_via.c b/drivers/scsi/sata_via.c
index 1c9e2f3..c6975c5 100644
--- a/drivers/scsi/sata_via.c
+++ b/drivers/scsi/sata_via.c
@@ -103,6 +103,7 @@ static struct scsi_host_template svia_sh
 	.proc_name		= DRV_NAME,
 	.dma_boundary		= ATA_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
+	.slave_destroy		= ata_scsi_slave_destroy,
 	.bios_param		= ata_std_bios_param,
 };
 
diff --git a/drivers/scsi/sata_vsc.c b/drivers/scsi/sata_vsc.c
index 438e7c6..22ca7b8 100644
--- a/drivers/scsi/sata_vsc.c
+++ b/drivers/scsi/sata_vsc.c
@@ -279,6 +279,7 @@ static struct scsi_host_template vsc_sat
 	.proc_name		= DRV_NAME,
 	.dma_boundary		= ATA_DMA_BOUNDARY,
 	.slave_configure	= ata_scsi_slave_config,
+	.slave_destroy		= ata_scsi_slave_destroy,
 	.bios_param		= ata_std_bios_param,
 };
 
-- 
1.3.2

[PATCH 06/13] libata-hp: implement bootplug

[Tejun Heo]

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>

---

 drivers/scsi/libata-core.c |   49 +++++++++++++++++++++++++++++++-------------
 drivers/scsi/libata-eh.c   |   27 ++++++++++++++++--------
 2 files changed, 52 insertions(+), 24 deletions(-)

3e706399b03bd237d087d731d4b1b029e546b33d
diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index c61cfc7..a42877e 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -5419,7 +5419,7 @@ static struct ata_port * ata_host_add(co
 
 	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_prob
 		}
 		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_prob
 			 * 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 733dfa5..70c132b 100644
--- a/drivers/scsi/libata-eh.c
+++ b/drivers/scsi/libata-eh.c
@@ -287,11 +287,14 @@ void ata_scsi_error(struct Scsi_Host *ho
 	/* 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 
 	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 
 	}
 
  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_
 	       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);
 }
-- 
1.3.2

[PATCH 04/13] libata-hp: implement warmplug

[Tejun Heo]

Implement warmplug.  User-initiated unplug can be detected by
hostt->slave_destroy() and plug by transportt->user_scan().  This
patch only implements the two callbacks.  The next function will hook
them.

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

---

 drivers/scsi/libata-core.c |    1 
 drivers/scsi/libata-scsi.c |   89 ++++++++++++++++++++++++++++++++++++++++++++
 include/linux/libata.h     |    1 
 3 files changed, 91 insertions(+), 0 deletions(-)

83c47bcb3c533180a6dda78152334de50065358a
diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index 8df8ecc..c61cfc7 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -5942,6 +5942,7 @@ EXPORT_SYMBOL_GPL(ata_port_queue_task);
 EXPORT_SYMBOL_GPL(ata_scsi_ioctl);
 EXPORT_SYMBOL_GPL(ata_scsi_queuecmd);
 EXPORT_SYMBOL_GPL(ata_scsi_slave_config);
+EXPORT_SYMBOL_GPL(ata_scsi_slave_destroy);
 EXPORT_SYMBOL_GPL(ata_scsi_change_queue_depth);
 EXPORT_SYMBOL_GPL(ata_scsi_release);
 EXPORT_SYMBOL_GPL(ata_host_intr);
diff --git a/drivers/scsi/libata-scsi.c b/drivers/scsi/libata-scsi.c
index 1256399..7c1ac58 100644
--- a/drivers/scsi/libata-scsi.c
+++ b/drivers/scsi/libata-scsi.c
@@ -57,6 +57,8 @@ static struct ata_device * __ata_scsi_fi
 					const struct scsi_device *scsidev);
 static struct ata_device * ata_scsi_find_dev(struct ata_port *ap,
 					    const struct scsi_device *scsidev);
+static int ata_scsi_user_scan(struct Scsi_Host *shost, unsigned int channel,
+			      unsigned int id, unsigned int lun);
 
 
 #define RW_RECOVERY_MPAGE 0x1
@@ -727,6 +729,40 @@ int ata_scsi_slave_config(struct scsi_de
 }
 
 /**
+ *	ata_scsi_slave_destroy - SCSI device is about to be destroyed
+ *	@sdev: SCSI device to be destroyed
+ *
+ *	@sdev is about to be destroyed for hot/warm unplugging.  If
+ *	this unplugging was initiated by libata as indicated by NULL
+ *	dev->sdev, this function doesn't have to do anything.
+ *	Otherwise, SCSI layer initiated warm-unplug is in progress.
+ *	Clear dev->sdev, schedule the device for ATA detach and invoke
+ *	EH.
+ *
+ *	LOCKING:
+ *	Defined by SCSI layer.  We don't really care.
+ */
+void ata_scsi_slave_destroy(struct scsi_device *sdev)
+{
+	struct ata_port *ap = ata_shost_to_port(sdev->host);
+	unsigned long flags;
+	struct ata_device *dev;
+
+	if (!ap->ops->error_handler)
+		return;
+
+	spin_lock_irqsave(&ap->host_set->lock, flags);
+	dev = __ata_scsi_find_dev(ap, sdev);
+	if (dev && dev->sdev) {
+		/* SCSI device already in CANCEL state, no need to offline it */
+		dev->sdev = NULL;
+		dev->flags |= ATA_DFLAG_DETACH;
+		ata_port_schedule_eh(ap);
+	}
+	spin_unlock_irqrestore(&ap->host_set->lock, flags);
+}
+
+/**
  *	ata_scsi_change_queue_depth - SCSI callback for queue depth config
  *	@sdev: SCSI device to configure queue depth for
  *	@queue_depth: new queue depth
@@ -2902,3 +2938,56 @@ void ata_scsi_hotplug(void *data)
 
 	DPRINTK("EXIT\n");
 }
+
+/**
+ *	ata_scsi_user_scan - indication for user-initiated bus scan
+ *	@shost: SCSI host to scan
+ *	@channel: Channel to scan
+ *	@id: ID to scan
+ *	@lun: LUN to scan
+ *
+ *	This function is called when user explicitly requests bus
+ *	scan.  Set probe pending flag and invoke EH.
+ *
+ *	LOCKING:
+ *	SCSI layer (we don't care)
+ *
+ *	RETURNS:
+ *	Zero.
+ */
+static int ata_scsi_user_scan(struct Scsi_Host *shost, unsigned int channel,
+			      unsigned int id, unsigned int lun)
+{
+	struct ata_port *ap = ata_shost_to_port(shost);
+	unsigned long flags;
+	int rc = 0;
+
+	if (!ap->ops->error_handler)
+		return -EOPNOTSUPP;
+
+	if ((channel != SCAN_WILD_CARD && channel != 0) ||
+	    (lun != SCAN_WILD_CARD && lun != 0))
+		return -EINVAL;
+
+	spin_lock_irqsave(&ap->host_set->lock, flags);
+
+	if (id == SCAN_WILD_CARD) {
+		ap->eh_info.probe_mask |= (1 << ATA_MAX_DEVICES) - 1;
+		ap->eh_info.action |= ATA_EH_SOFTRESET;
+	} else {
+		struct ata_device *dev = ata_find_dev(ap, id);
+
+		if (dev) {
+			ap->eh_info.probe_mask |= 1 << dev->devno;
+			ap->eh_info.action |= ATA_EH_SOFTRESET;
+		} else
+			rc = -EINVAL;
+	}
+
+	if (rc == 0)
+		ata_port_schedule_eh(ap);
+
+	spin_unlock_irqrestore(&ap->host_set->lock, flags);
+
+	return rc;
+}
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 4071156..74786c3 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -734,6 +734,7 @@ extern int ata_std_bios_param(struct scs
 			      struct block_device *bdev,
 			      sector_t capacity, int geom[]);
 extern int ata_scsi_slave_config(struct scsi_device *sdev);
+extern void ata_scsi_slave_destroy(struct scsi_device *sdev);
 extern int ata_scsi_change_queue_depth(struct scsi_device *sdev,
 				       int queue_depth);
 extern struct ata_device *ata_dev_pair(struct ata_device *adev);
-- 
1.3.2

[PATCH 08/13] ata_piix: convert ata_piix to new probing mechanism

[Tejun Heo]

Convert ata_piix to new probing mechanism.  Automatic hotplug is not
supported due to hardware limitation (no PHY event interrupt), but
warm plugging works.

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

---

 drivers/scsi/ata_piix.c |   87 +++++++++++++++++------------------------------
 1 files changed, 32 insertions(+), 55 deletions(-)

ccc4672aff1861a9c80ed9e8ec11dc304b31d307
diff --git a/drivers/scsi/ata_piix.c b/drivers/scsi/ata_piix.c
index 54c2e52..521b718 100644
--- a/drivers/scsi/ata_piix.c
+++ b/drivers/scsi/ata_piix.c
@@ -146,11 +146,10 @@ struct piix_map_db {
 
 static int piix_init_one (struct pci_dev *pdev,
 				    const struct pci_device_id *ent);
-
-static int piix_pata_probe_reset(struct ata_port *ap, unsigned int *classes);
-static int piix_sata_probe_reset(struct ata_port *ap, unsigned int *classes);
 static void piix_set_piomode (struct ata_port *ap, struct ata_device *adev);
 static void piix_set_dmamode (struct ata_port *ap, struct ata_device *adev);
+static void piix_pata_error_handler(struct ata_port *ap);
+static void piix_sata_error_handler(struct ata_port *ap);
 
 static unsigned int in_module_init = 1;
 
@@ -237,8 +236,6 @@ static const struct ata_port_operations 
 	.exec_command		= ata_exec_command,
 	.dev_select		= ata_std_dev_select,
 
-	.probe_reset		= piix_pata_probe_reset,
-
 	.bmdma_setup		= ata_bmdma_setup,
 	.bmdma_start		= ata_bmdma_start,
 	.bmdma_stop		= ata_bmdma_stop,
@@ -249,7 +246,7 @@ static const struct ata_port_operations 
 
 	.freeze			= ata_bmdma_freeze,
 	.thaw			= ata_bmdma_thaw,
-	.error_handler		= ata_bmdma_error_handler,
+	.error_handler		= piix_pata_error_handler,
 	.post_internal_cmd	= ata_bmdma_post_internal_cmd,
 
 	.irq_handler		= ata_interrupt,
@@ -269,8 +266,6 @@ static const struct ata_port_operations 
 	.exec_command		= ata_exec_command,
 	.dev_select		= ata_std_dev_select,
 
-	.probe_reset		= piix_sata_probe_reset,
-
 	.bmdma_setup		= ata_bmdma_setup,
 	.bmdma_start		= ata_bmdma_start,
 	.bmdma_stop		= ata_bmdma_stop,
@@ -281,7 +276,7 @@ static const struct ata_port_operations 
 
 	.freeze			= ata_bmdma_freeze,
 	.thaw			= ata_bmdma_thaw,
-	.error_handler		= ata_bmdma_error_handler,
+	.error_handler		= piix_sata_error_handler,
 	.post_internal_cmd	= ata_bmdma_post_internal_cmd,
 
 	.irq_handler		= ata_interrupt,
@@ -466,59 +461,51 @@ cbl40:
 }
 
 /**
- *	piix_pata_probeinit - probeinit for PATA host controller
+ *	piix_pata_prereset - prereset for PATA host controller
  *	@ap: Target port
  *
- *	Probeinit including cable detection.
- *
- *	LOCKING:
- *	None (inherited from caller).
- */
-static void piix_pata_probeinit(struct ata_port *ap)
-{
-	piix_pata_cbl_detect(ap);
-	ata_std_probeinit(ap);
-}
-
-/**
- *	piix_pata_probe_reset - Perform reset on PATA port and classify
- *	@ap: Port to reset
- *	@classes: Resulting classes of attached devices
- *
- *	Reset PATA phy and classify attached devices.
+ *	Prereset including cable detection.
  *
  *	LOCKING:
  *	None (inherited from caller).
  */
-static int piix_pata_probe_reset(struct ata_port *ap, unsigned int *classes)
+static int piix_pata_prereset(struct ata_port *ap)
 {
 	struct pci_dev *pdev = to_pci_dev(ap->host_set->dev);
 
 	if (!pci_test_config_bits(pdev, &piix_enable_bits[ap->hard_port_no])) {
 		ata_port_printk(ap, KERN_INFO, "port disabled. ignoring.\n");
+		ap->eh_context.i.action &= ~ATA_EH_RESET_MASK;
 		return 0;
 	}
 
-	return ata_drive_probe_reset(ap, piix_pata_probeinit,
-				     ata_std_softreset, NULL,
-				     ata_std_postreset, classes);
+	piix_pata_cbl_detect(ap);
+
+	return ata_std_prereset(ap);
+}
+
+static void piix_pata_error_handler(struct ata_port *ap)
+{
+	ata_bmdma_drive_eh(ap, piix_pata_prereset, ata_std_softreset, NULL,
+			   ata_std_postreset);
 }
 
 /**
- *	piix_sata_probe - Probe PCI device for present SATA devices
- *	@ap: Port associated with the PCI device we wish to probe
+ *	piix_sata_prereset - prereset for SATA host controller
+ *	@ap: Target port
  *
  *	Reads and configures SATA PCI device's PCI config register
  *	Port Configuration and Status (PCS) to determine port and
- *	device availability.
+ *	device availability.  Return -ENODEV to skip reset if no
+ *	device is present.
  *
  *	LOCKING:
  *	None (inherited from caller).
  *
  *	RETURNS:
- *	Mask of avaliable devices on the port.
+ *	0 if device is present, -ENODEV otherwise.
  */
-static unsigned int piix_sata_probe (struct ata_port *ap)
+static int piix_sata_prereset(struct ata_port *ap)
 {
 	struct pci_dev *pdev = to_pci_dev(ap->host_set->dev);
 	const unsigned int *map = ap->host_set->private_data;
@@ -560,29 +547,19 @@ static unsigned int piix_sata_probe (str
 	DPRINTK("ata%u: LEAVE, pcs=0x%x present_mask=0x%x\n",
 		ap->id, pcs, present_mask);
 
-	return present_mask;
-}
-
-/**
- *	piix_sata_probe_reset - Perform reset on SATA port and classify
- *	@ap: Port to reset
- *	@classes: Resulting classes of attached devices
- *
- *	Reset SATA phy and classify attached devices.
- *
- *	LOCKING:
- *	None (inherited from caller).
- */
-static int piix_sata_probe_reset(struct ata_port *ap, unsigned int *classes)
-{
-	if (!piix_sata_probe(ap)) {
+	if (!present_mask) {
 		ata_port_printk(ap, KERN_INFO, "SATA port has no device.\n");
+		ap->eh_context.i.action &= ~ATA_EH_RESET_MASK;
 		return 0;
 	}
 
-	return ata_drive_probe_reset(ap, ata_std_probeinit,
-				     ata_std_softreset, NULL,
-				     ata_std_postreset, classes);
+	return ata_std_prereset(ap);
+}
+
+static void piix_sata_error_handler(struct ata_port *ap)
+{
+	ata_bmdma_drive_eh(ap, piix_sata_prereset, ata_std_softreset, NULL,
+			   ata_std_postreset);
 }
 
 /**
-- 
1.3.2

[PATCH 13/13] libata-hp: move ata_do_reset() to libata-eh.c

[Tejun Heo]

With ops->probe_init() gone, no user is left in libata-core.c.  Move
ata_do_reset() to libata-eh.c and make it static.

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

---

 drivers/scsi/libata-core.c |   28 ----------------------------
 drivers/scsi/libata-eh.c   |   28 ++++++++++++++++++++++++++++
 drivers/scsi/libata.h      |    2 --
 3 files changed, 28 insertions(+), 30 deletions(-)

d87fa38e70853a9607dc34a02d15cf5f149f49f2
diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index 30a6020..40d1612 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -2783,34 +2783,6 @@ void ata_std_postreset(struct ata_port *
 	DPRINTK("EXIT\n");
 }
 
-int ata_do_reset(struct ata_port *ap, ata_reset_fn_t reset,
-		 unsigned int *classes)
-{
-	int i, rc;
-
-	for (i = 0; i < ATA_MAX_DEVICES; i++)
-		classes[i] = ATA_DEV_UNKNOWN;
-
-	rc = reset(ap, classes);
-	if (rc)
-		return rc;
-
-	/* If any class isn't ATA_DEV_UNKNOWN, consider classification
-	 * is complete and convert all ATA_DEV_UNKNOWN to
-	 * ATA_DEV_NONE.
-	 */
-	for (i = 0; i < ATA_MAX_DEVICES; i++)
-		if (classes[i] != ATA_DEV_UNKNOWN)
-			break;
-
-	if (i < ATA_MAX_DEVICES)
-		for (i = 0; i < ATA_MAX_DEVICES; i++)
-			if (classes[i] == ATA_DEV_UNKNOWN)
-				classes[i] = ATA_DEV_NONE;
-
-	return 0;
-}
-
 /**
  *	ata_dev_same_device - Determine whether new ID matches configured device
  *	@dev: device to compare against
diff --git a/drivers/scsi/libata-eh.c b/drivers/scsi/libata-eh.c
index 30a83a5..d4b80b6 100644
--- a/drivers/scsi/libata-eh.c
+++ b/drivers/scsi/libata-eh.c
@@ -1355,6 +1355,34 @@ static void ata_eh_report(struct ata_por
 	}
 }
 
+static int ata_do_reset(struct ata_port *ap, ata_reset_fn_t reset,
+			unsigned int *classes)
+{
+	int i, rc;
+
+	for (i = 0; i < ATA_MAX_DEVICES; i++)
+		classes[i] = ATA_DEV_UNKNOWN;
+
+	rc = reset(ap, classes);
+	if (rc)
+		return rc;
+
+	/* If any class isn't ATA_DEV_UNKNOWN, consider classification
+	 * is complete and convert all ATA_DEV_UNKNOWN to
+	 * ATA_DEV_NONE.
+	 */
+	for (i = 0; i < ATA_MAX_DEVICES; i++)
+		if (classes[i] != ATA_DEV_UNKNOWN)
+			break;
+
+	if (i < ATA_MAX_DEVICES)
+		for (i = 0; i < ATA_MAX_DEVICES; i++)
+			if (classes[i] == ATA_DEV_UNKNOWN)
+				classes[i] = ATA_DEV_NONE;
+
+	return 0;
+}
+
 static int ata_eh_followup_srst_needed(int rc, int classify,
 				       const unsigned int *classes)
 {
diff --git a/drivers/scsi/libata.h b/drivers/scsi/libata.h
index 0586b0c..1dd496f 100644
--- a/drivers/scsi/libata.h
+++ b/drivers/scsi/libata.h
@@ -57,8 +57,6 @@ extern int sata_down_spd_limit(struct at
 extern int sata_set_spd_needed(struct ata_port *ap);
 extern int ata_down_xfermask_limit(struct ata_device *dev, int force_pio0);
 extern int ata_set_mode(struct ata_port *ap, struct ata_device **r_failed_dev);
-extern int ata_do_reset(struct ata_port *ap, ata_reset_fn_t reset,
-			unsigned int *classes);
 extern void ata_qc_free(struct ata_queued_cmd *qc);
 extern void ata_qc_issue(struct ata_queued_cmd *qc);
 extern void __ata_qc_complete(struct ata_queued_cmd *qc);
-- 
1.3.2

Re: [PATCH 13/13] libata-hp: move ata_do_reset() to libata-eh.c

[Jeff Garzik]

Tejun Heo wrote:
> With ops->probe_init() gone, no user is left in libata-core.c.  Move
> ata_do_reset() to libata-eh.c and make it static.
> 
> Signed-off-by: Tejun Heo <htejun@gmail.com>

ACK 4-13

Re: [PATCH 13/13] libata-hp: move ata_do_reset() to libata-eh.c

[Jeff Garzik]

FWIW, if you would prefer to append update patches to the patchset, 
rather than regenerating three patchsets, that's fine with me.

	Jeff

Re: [PATCH 13/13] libata-hp: move ata_do_reset() to libata-eh.c

[Tejun Heo]

Jeff Garzik wrote:
> FWIW, if you would prefer to append update patches to the patchset, 
> rather than regenerating three patchsets, that's fine with me.

I'd love that.

Thanks.

-- 
tejun

[PATCH 12/13] libata-hp: killl ops->probe_reset

[Tejun Heo]

Now that all drivers implementing new EH are converted to new probing
mechanism, ops->probe_reset doesn't have any user.  Kill it.

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

---

 drivers/scsi/libata-core.c |  187 +++-----------------------------------------
 include/linux/libata.h     |    8 --
 2 files changed, 13 insertions(+), 182 deletions(-)

52783c5dcc8d317bc8c3e2692d366e8a305abada
diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index 01f2c59..30a6020 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -1479,31 +1479,21 @@ static int ata_bus_probe(struct ata_port
 	down_xfermask = 0;
 
 	/* reset and determine device classes */
-	for (i = 0; i < ATA_MAX_DEVICES; i++)
-		classes[i] = ATA_DEV_UNKNOWN;
+	ap->ops->phy_reset(ap);
 
-	if (ap->ops->probe_reset) {
-		rc = ap->ops->probe_reset(ap, classes);
-		if (rc) {
-			ata_port_printk(ap, KERN_ERR,
-					"reset failed (errno=%d)\n", rc);
-			return rc;
-		}
-	} else {
-		ap->ops->phy_reset(ap);
+	for (i = 0; i < ATA_MAX_DEVICES; i++) {
+		dev = &ap->device[i];
 
-		for (i = 0; i < ATA_MAX_DEVICES; i++) {
-			if (!(ap->flags & ATA_FLAG_DISABLED))
-				classes[i] = ap->device[i].class;
-			ap->device[i].class = ATA_DEV_UNKNOWN;
-		}
+		if (!(ap->flags & ATA_FLAG_DISABLED) &&
+		    dev->class != ATA_DEV_UNKNOWN)
+			classes[dev->devno] = dev->class;
+		else
+			classes[dev->devno] = ATA_DEV_NONE;
 
-		ata_port_probe(ap);
+		dev->class = ATA_DEV_UNKNOWN;
 	}
 
-	for (i = 0; i < ATA_MAX_DEVICES; i++)
-		if (classes[i] == ATA_DEV_UNKNOWN)
-			classes[i] = ATA_DEV_NONE;
+	ata_port_probe(ap);
 
 	/* after the reset the device state is PIO 0 and the controller
 	   state is undefined. Record the mode */
@@ -2610,37 +2600,11 @@ int ata_std_prereset(struct ata_port *ap
 }
 
 /**
- *	ata_std_probeinit - initialize probing
- *	@ap: port to be probed
- *
- *	@ap is about to be probed.  Initialize it.  This function is
- *	to be used as standard callback for ata_drive_probe_reset().
- *
- *	NOTE!!! Do not use this function as probeinit if a low level
- *	driver implements only hardreset.  Just pass NULL as probeinit
- *	in that case.  Using this function is probably okay but doing
- *	so makes reset sequence different from the original
- *	->phy_reset implementation and Jeff nervous.  :-P
- */
-void ata_std_probeinit(struct ata_port *ap)
-{
-	static const unsigned long deb_timing[] = { 5, 100, 5000 };
-
-	/* resume link */
-	sata_phy_resume(ap, deb_timing);
-
-	/* wait for device */
-	if (ata_port_online(ap))
-		ata_busy_sleep(ap, ATA_TMOUT_BOOT_QUICK, ATA_TMOUT_BOOT);
-}
-
-/**
  *	ata_std_softreset - reset host port via ATA SRST
  *	@ap: port to reset
  *	@classes: resulting classes of attached devices
  *
- *	Reset host port using ATA SRST.  This function is to be used
- *	as standard callback for ata_drive_*_reset() functions.
+ *	Reset host port using ATA SRST.
  *
  *	LOCKING:
  *	Kernel thread context (may sleep)
@@ -2695,8 +2659,6 @@ int ata_std_softreset(struct ata_port *a
  *	@class: resulting class of attached device
  *
  *	SATA phy-reset host port using DET bits of SControl register.
- *	This function is to be used as standard callback for
- *	ata_drive_*_reset().
  *
  *	LOCKING:
  *	Kernel thread context (may sleep)
@@ -2775,9 +2737,6 @@ int sata_std_hardreset(struct ata_port *
  *	the device might have been reset more than once using
  *	different reset methods before postreset is invoked.
  *
- *	This function is to be used as standard callback for
- *	ata_drive_*_reset().
- *
  *	LOCKING:
  *	Kernel thread context (may sleep)
  */
@@ -2824,32 +2783,6 @@ void ata_std_postreset(struct ata_port *
 	DPRINTK("EXIT\n");
 }
 
-/**
- *	ata_std_probe_reset - standard probe reset method
- *	@ap: prot to perform probe-reset
- *	@classes: resulting classes of attached devices
- *
- *	The stock off-the-shelf ->probe_reset method.
- *
- *	LOCKING:
- *	Kernel thread context (may sleep)
- *
- *	RETURNS:
- *	0 on success, -errno otherwise.
- */
-int ata_std_probe_reset(struct ata_port *ap, unsigned int *classes)
-{
-	ata_reset_fn_t hardreset;
-
-	hardreset = NULL;
-	if (sata_scr_valid(ap))
-		hardreset = sata_std_hardreset;
-
-	return ata_drive_probe_reset(ap, ata_std_probeinit,
-				     ata_std_softreset, hardreset,
-				     ata_std_postreset, classes);
-}
-
 int ata_do_reset(struct ata_port *ap, ata_reset_fn_t reset,
 		 unsigned int *classes)
 {
@@ -2879,97 +2812,6 @@ int ata_do_reset(struct ata_port *ap, at
 }
 
 /**
- *	ata_drive_probe_reset - Perform probe reset with given methods
- *	@ap: port to reset
- *	@probeinit: probeinit method (can be NULL)
- *	@softreset: softreset method (can be NULL)
- *	@hardreset: hardreset method (can be NULL)
- *	@postreset: postreset method (can be NULL)
- *	@classes: resulting classes of attached devices
- *
- *	Reset the specified port and classify attached devices using
- *	given methods.  This function prefers softreset but tries all
- *	possible reset sequences to reset and classify devices.  This
- *	function is intended to be used for constructing ->probe_reset
- *	callback by low level drivers.
- *
- *	Reset methods should follow the following rules.
- *
- *	- Return 0 on sucess, -errno on failure.
- *	- If classification is supported, fill classes[] with
- *	  recognized class codes.
- *	- If classification is not supported, leave classes[] alone.
- *
- *	LOCKING:
- *	Kernel thread context (may sleep)
- *
- *	RETURNS:
- *	0 on success, -EINVAL if no reset method is avaliable, -ENODEV
- *	if classification fails, and any error code from reset
- *	methods.
- */
-int ata_drive_probe_reset(struct ata_port *ap, ata_probeinit_fn_t probeinit,
-			  ata_reset_fn_t softreset, ata_reset_fn_t hardreset,
-			  ata_postreset_fn_t postreset, unsigned int *classes)
-{
-	int rc = -EINVAL;
-
-	ata_eh_freeze_port(ap);
-
-	if (probeinit)
-		probeinit(ap);
-
-	if (softreset && !sata_set_spd_needed(ap)) {
-		rc = ata_do_reset(ap, softreset, classes);
-		if (rc == 0 && classes[0] != ATA_DEV_UNKNOWN)
-			goto done;
-		ata_port_printk(ap, KERN_INFO, "softreset failed, "
-				"will try hardreset in 5 secs\n");
-		ssleep(5);
-	}
-
-	if (!hardreset)
-		goto done;
-
-	while (1) {
-		rc = ata_do_reset(ap, hardreset, classes);
-		if (rc == 0) {
-			if (classes[0] != ATA_DEV_UNKNOWN)
-				goto done;
-			break;
-		}
-
-		if (sata_down_spd_limit(ap))
-			goto done;
-
-		ata_port_printk(ap, KERN_INFO, "hardreset failed, "
-				"will retry in 5 secs\n");
-		ssleep(5);
-	}
-
-	if (softreset) {
-		ata_port_printk(ap, KERN_INFO,
-				"hardreset succeeded without classification, "
-				"will retry softreset in 5 secs\n");
-		ssleep(5);
-
-		rc = ata_do_reset(ap, softreset, classes);
-	}
-
- done:
-	if (rc == 0) {
-		if (postreset)
-			postreset(ap, classes);
-
-		ata_eh_thaw_port(ap);
-
-		if (classes[0] == ATA_DEV_UNKNOWN)
-			rc = -ENODEV;
-	}
-	return rc;
-}
-
-/**
  *	ata_dev_same_device - Determine whether new ID matches configured device
  *	@dev: device to compare against
  *	@new_class: class of the new device
@@ -5419,7 +5261,7 @@ static struct ata_port * ata_host_add(co
 
 	DPRINTK("ENTER\n");
 
-	if (!ent->port_ops->probe_reset && !ent->port_ops->error_handler &&
+	if (!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);
@@ -5551,7 +5393,7 @@ int ata_device_add(const struct ata_prob
 			 */
 		}
 
-		if (!ap->ops->probe_reset) {
+		if (ap->ops->error_handler) {
 			unsigned long flags;
 
 			ata_port_probe(ap);
@@ -5998,13 +5840,10 @@ EXPORT_SYMBOL_GPL(sata_phy_resume);
 EXPORT_SYMBOL_GPL(sata_phy_reset);
 EXPORT_SYMBOL_GPL(__sata_phy_reset);
 EXPORT_SYMBOL_GPL(ata_bus_reset);
-EXPORT_SYMBOL_GPL(ata_std_probeinit);
 EXPORT_SYMBOL_GPL(ata_std_prereset);
 EXPORT_SYMBOL_GPL(ata_std_softreset);
 EXPORT_SYMBOL_GPL(sata_std_hardreset);
 EXPORT_SYMBOL_GPL(ata_std_postreset);
-EXPORT_SYMBOL_GPL(ata_std_probe_reset);
-EXPORT_SYMBOL_GPL(ata_drive_probe_reset);
 EXPORT_SYMBOL_GPL(ata_dev_revalidate);
 EXPORT_SYMBOL_GPL(ata_dev_classify);
 EXPORT_SYMBOL_GPL(ata_dev_pair);
diff --git a/include/linux/libata.h b/include/linux/libata.h
index f11ba27..a2a33a9 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -303,7 +303,6 @@ struct ata_queued_cmd;
 
 /* typedefs */
 typedef void (*ata_qc_cb_t) (struct ata_queued_cmd *qc);
-typedef void (*ata_probeinit_fn_t)(struct ata_port *ap);
 typedef int (*ata_prereset_fn_t)(struct ata_port *ap);
 typedef int (*ata_reset_fn_t)(struct ata_port *ap, unsigned int *classes);
 typedef void (*ata_postreset_fn_t)(struct ata_port *ap, unsigned int *classes);
@@ -553,7 +552,6 @@ struct ata_port_operations {
 
 	void (*phy_reset) (struct ata_port *ap); /* obsolete */
 	void (*set_mode) (struct ata_port *ap);
-	int (*probe_reset) (struct ata_port *ap, unsigned int *classes);
 
 	void (*post_set_mode) (struct ata_port *ap);
 
@@ -628,11 +626,6 @@ extern void ata_bus_reset(struct ata_por
 extern int sata_set_spd(struct ata_port *ap);
 extern int sata_phy_debounce(struct ata_port *ap, const unsigned long *param);
 extern int sata_phy_resume(struct ata_port *ap, const unsigned long *param);
-extern int ata_drive_probe_reset(struct ata_port *ap,
-			ata_probeinit_fn_t probeinit,
-			ata_reset_fn_t softreset, ata_reset_fn_t hardreset,
-			ata_postreset_fn_t postreset, unsigned int *classes);
-extern void ata_std_probeinit(struct ata_port *ap);
 extern int ata_std_prereset(struct ata_port *ap);
 extern int ata_std_softreset(struct ata_port *ap, unsigned int *classes);
 extern int sata_std_hardreset(struct ata_port *ap, unsigned int *class);
@@ -688,7 +681,6 @@ extern void ata_std_dev_select (struct a
 extern u8 ata_check_status(struct ata_port *ap);
 extern u8 ata_altstatus(struct ata_port *ap);
 extern void ata_exec_command(struct ata_port *ap, const struct ata_taskfile *tf);
-extern int ata_std_probe_reset(struct ata_port *ap, unsigned int *classes);
 extern int ata_port_start (struct ata_port *ap);
 extern void ata_port_stop (struct ata_port *ap);
 extern void ata_host_stop (struct ata_host_set *host_set);
-- 
1.3.2

[PATCH 11/13] sata_sil24: convert to new probing mechanism and add hotplug support

[Tejun Heo]

Convert to new probing mechanism and add hotplug support by enabling
PORT_IRQ_PHYRDY_CHG, marking ehi for hotplug and scheduling EH on
PORT_IRQ_PHYRDY_CHG or PORT_IRQ_DEV_XCHG.

Sil3124/32 family of controllers don't have any mechanism to wait for
the first D2H FIS after hotplug, so ATA_FLAG_SKIP_D2H_BSY is used.

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

---

 drivers/scsi/sata_sil24.c |   27 ++++++++-------------------
 1 files changed, 8 insertions(+), 19 deletions(-)

0542925b25676543e8384edf454668f89227e905
diff --git a/drivers/scsi/sata_sil24.c b/drivers/scsi/sata_sil24.c
index d4ca6d6..97e9339 100644
--- a/drivers/scsi/sata_sil24.c
+++ b/drivers/scsi/sata_sil24.c
@@ -159,7 +159,8 @@ enum {
 	PORT_IRQ_SDB_NOTIFY	= (1 << 11), /* SDB notify received */
 
 	DEF_PORT_IRQ		= PORT_IRQ_COMPLETE | PORT_IRQ_ERROR |
-				  PORT_IRQ_DEV_XCHG | PORT_IRQ_UNK_FIS,
+				  PORT_IRQ_PHYRDY_CHG | PORT_IRQ_DEV_XCHG |
+				  PORT_IRQ_UNK_FIS,
 
 	/* bits[27:16] are unmasked (raw) */
 	PORT_IRQ_RAW_SHIFT	= 16,
@@ -228,7 +229,7 @@ enum {
 	/* host flags */
 	SIL24_COMMON_FLAGS	= ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY |
 				  ATA_FLAG_MMIO | ATA_FLAG_PIO_DMA |
-				  ATA_FLAG_NCQ,
+				  ATA_FLAG_NCQ | ATA_FLAG_SKIP_D2H_BSY,
 	SIL24_FLAG_PCIX_IRQ_WOC	= (1 << 24), /* IRQ loss errata on PCI-X */
 
 	IRQ_STAT_4PORTS		= 0xf,
@@ -325,7 +326,6 @@ static u8 sil24_check_status(struct ata_
 static u32 sil24_scr_read(struct ata_port *ap, unsigned sc_reg);
 static void sil24_scr_write(struct ata_port *ap, unsigned sc_reg, u32 val);
 static void sil24_tf_read(struct ata_port *ap, struct ata_taskfile *tf);
-static int sil24_probe_reset(struct ata_port *ap, unsigned int *classes);
 static void sil24_qc_prep(struct ata_queued_cmd *qc);
 static unsigned int sil24_qc_issue(struct ata_queued_cmd *qc);
 static void sil24_irq_clear(struct ata_port *ap);
@@ -385,8 +385,6 @@ static const struct ata_port_operations 
 
 	.tf_read		= sil24_tf_read,
 
-	.probe_reset		= sil24_probe_reset,
-
 	.qc_prep		= sil24_qc_prep,
 	.qc_issue		= sil24_qc_issue,
 
@@ -635,13 +633,6 @@ static int sil24_hardreset(struct ata_po
 	return -EIO;
 }
 
-static int sil24_probe_reset(struct ata_port *ap, unsigned int *classes)
-{
-	return ata_drive_probe_reset(ap, ata_std_probeinit,
-				     sil24_softreset, sil24_hardreset,
-				     ata_std_postreset, classes);
-}
-
 static inline void sil24_fill_sg(struct ata_queued_cmd *qc,
 				 struct sil24_sge *sge)
 {
@@ -772,13 +763,11 @@ static void sil24_error_intr(struct ata_
 
 	ata_ehi_push_desc(ehi, "irq_stat 0x%08x", irq_stat);
 
-	if (irq_stat & PORT_IRQ_DEV_XCHG) {
-		ehi->err_mask |= AC_ERR_ATA_BUS;
-		/* sil24 doesn't recover very well from phy
-		 * disconnection with a softreset.  Force hardreset.
-		 */
-		ehi->action |= ATA_EH_HARDRESET;
-		ata_ehi_push_desc(ehi, ", device_exchanged");
+	if (irq_stat & (PORT_IRQ_PHYRDY_CHG | PORT_IRQ_DEV_XCHG)) {
+		ata_ehi_hotplugged(ehi);
+		ata_ehi_push_desc(ehi, ", %s",
+			       irq_stat & PORT_IRQ_PHYRDY_CHG ?
+			       "PHY RDY changed" : "device exchanged");
 		freeze = 1;
 	}
 
-- 
1.3.2