From 341963b909a01d2f38d86f5db8dd1f8c80bd6dbf Mon Sep 17 00:00:00 2001
From: Tejun Heo <htejun@gmail.com>
Date: Fri, 10 Feb 2006 15:10:48 +0900
Subject: [PATCH] libata: add ATA_QCFLAG_EH_SCHEDULED

Add ATA_QCFLAG_EH_SCHEDULED.  If this flag is set, the qc is owned by
EH and normal completion path is not allowed to finish it.  This patch
doesn't actually use this flag.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
---
 drivers/scsi/libata-core.c | 33 ++++++++++++++++++++-------------
 drivers/scsi/libata-scsi.c |  2 +-
 drivers/scsi/libata.h      |  1 +
 include/linux/libata.h     |  1 +
 4 files changed, 23 insertions(+), 14 deletions(-)

diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index 22db7393225..977a53dd167 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -3620,19 +3620,7 @@ void ata_qc_free(struct ata_queued_cmd *qc)
 	}
 }
 
-/**
- *	ata_qc_complete - Complete an active ATA command
- *	@qc: Command to complete
- *	@err_mask: ATA Status register contents
- *
- *	Indicate to the mid and upper layers that an ATA
- *	command has completed, with either an ok or not-ok status.
- *
- *	LOCKING:
- *	spin_lock_irqsave(host_set lock)
- */
-
-void ata_qc_complete(struct ata_queued_cmd *qc)
+inline void __ata_qc_complete(struct ata_queued_cmd *qc)
 {
 	assert(qc != NULL);	/* ata_qc_from_tag _might_ return NULL */
 	assert(qc->flags & ATA_QCFLAG_ACTIVE);
@@ -3650,6 +3638,25 @@ void ata_qc_complete(struct ata_queued_cmd *qc)
 	qc->complete_fn(qc);
 }
 
+/**
+ *	ata_qc_complete - Complete an active ATA command
+ *	@qc: Command to complete
+ *	@err_mask: ATA Status register contents
+ *
+ *	Indicate to the mid and upper layers that an ATA
+ *	command has completed, with either an ok or not-ok status.
+ *
+ *	LOCKING:
+ *	spin_lock_irqsave(host_set lock)
+ */
+void ata_qc_complete(struct ata_queued_cmd *qc)
+{
+	if (unlikely(qc->flags & ATA_QCFLAG_EH_SCHEDULED))
+		return;
+
+	__ata_qc_complete(qc);
+}
+
 static inline int ata_should_dma_map(struct ata_queued_cmd *qc)
 {
 	struct ata_port *ap = qc->ap;
diff --git a/drivers/scsi/libata-scsi.c b/drivers/scsi/libata-scsi.c
index b007bb40938..1df468eb2bf 100644
--- a/drivers/scsi/libata-scsi.c
+++ b/drivers/scsi/libata-scsi.c
@@ -770,7 +770,7 @@ static void __ata_eh_qc_complete(struct ata_queued_cmd *qc)
 
 	spin_lock_irqsave(&ap->host_set->lock, flags);
 	qc->scsidone = ata_eh_scsidone;
-	ata_qc_complete(qc);
+	__ata_qc_complete(qc);
 	assert(!ata_tag_valid(qc->tag));
 	spin_unlock_irqrestore(&ap->host_set->lock, flags);
 
diff --git a/drivers/scsi/libata.h b/drivers/scsi/libata.h
index 9d76923a225..1cd071a32e9 100644
--- a/drivers/scsi/libata.h
+++ b/drivers/scsi/libata.h
@@ -46,6 +46,7 @@ extern struct ata_queued_cmd *ata_qc_new_init(struct ata_port *ap,
 extern int ata_rwcmd_protocol(struct ata_queued_cmd *qc);
 extern void ata_qc_free(struct ata_queued_cmd *qc);
 extern unsigned int ata_qc_issue(struct ata_queued_cmd *qc);
+extern void __ata_qc_complete(struct ata_queued_cmd *qc);
 extern int ata_check_atapi_dma(struct ata_queued_cmd *qc);
 extern void ata_dev_select(struct ata_port *ap, unsigned int device,
                            unsigned int wait, unsigned int can_sleep);
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 68b3fe6f9a4..5c70a57f93e 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -169,6 +169,7 @@ enum {
 	ATA_QCFLAG_SG		= (1 << 3), /* have s/g table? */
 	ATA_QCFLAG_SINGLE	= (1 << 4), /* no s/g, just a single buffer */
 	ATA_QCFLAG_DMAMAP	= ATA_QCFLAG_SG | ATA_QCFLAG_SINGLE,
+	ATA_QCFLAG_EH_SCHEDULED = (1 << 5), /* EH scheduled */
 
 	/* various lengths of time */
 	ATA_TMOUT_EDD		= 5 * HZ,	/* heuristic */
-- 
cgit v1.2.3


From f29841e08fa20a7f2c8bc1b70306975299c66ee7 Mon Sep 17 00:00:00 2001
From: Tejun Heo <htejun@gmail.com>
Date: Fri, 10 Feb 2006 15:10:48 +0900
Subject: [PATCH] libata: implement ata_scsi_timed_out()

Implement ata_scsi_timed_out(), to be used as
scsi_host_template->eh_timed_out callback for all libata drivers.
Without this function, the following race exists.

If a qc completes after SCSI timer expires but before libata EH kicks
in, the qc gets completed but the scsicmd still gets passed to libata
EH resulting in ->eng_timeout invocation with NULL qc, which none is
handling properly.

This patch makes sure that scmd and qc share the same lifetime.
Original idea from Jeff Garzik <jgarzik@pobox.com>.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
---
 drivers/scsi/libata-core.c |  1 +
 drivers/scsi/libata-scsi.c | 41 +++++++++++++++++++++++++++++++++++++++++
 include/linux/libata.h     |  1 +
 3 files changed, 43 insertions(+)

diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index 977a53dd167..d53e0bce2be 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -4913,6 +4913,7 @@ EXPORT_SYMBOL_GPL(ata_ratelimit);
 EXPORT_SYMBOL_GPL(ata_busy_sleep);
 EXPORT_SYMBOL_GPL(ata_scsi_ioctl);
 EXPORT_SYMBOL_GPL(ata_scsi_queuecmd);
+EXPORT_SYMBOL_GPL(ata_scsi_timed_out);
 EXPORT_SYMBOL_GPL(ata_scsi_error);
 EXPORT_SYMBOL_GPL(ata_scsi_slave_config);
 EXPORT_SYMBOL_GPL(ata_scsi_release);
diff --git a/drivers/scsi/libata-scsi.c b/drivers/scsi/libata-scsi.c
index 1df468eb2bf..d67cc2fb569 100644
--- a/drivers/scsi/libata-scsi.c
+++ b/drivers/scsi/libata-scsi.c
@@ -716,6 +716,47 @@ int ata_scsi_slave_config(struct scsi_device *sdev)
 	return 0;	/* scsi layer doesn't check return value, sigh */
 }
 
+/**
+ *	ata_scsi_timed_out - SCSI layer time out callback
+ *	@cmd: timed out SCSI command
+ *
+ *	Handles SCSI layer timeout.  We race with normal completion of
+ *	the qc for @cmd.  If the qc is already gone, we lose and let
+ *	the scsi command finish (EH_HANDLED).  Otherwise, the qc has
+ *	timed out and EH should be invoked.  Prevent ata_qc_complete()
+ *	from finishing it by setting EH_SCHEDULED and return
+ *	EH_NOT_HANDLED.
+ *
+ *	LOCKING:
+ *	Called from timer context
+ *
+ *	RETURNS:
+ *	EH_HANDLED or EH_NOT_HANDLED
+ */
+enum scsi_eh_timer_return ata_scsi_timed_out(struct scsi_cmnd *cmd)
+{
+	struct Scsi_Host *host = cmd->device->host;
+	struct ata_port *ap = (struct ata_port *) &host->hostdata[0];
+	unsigned long flags;
+	struct ata_queued_cmd *qc;
+	enum scsi_eh_timer_return ret = EH_HANDLED;
+
+	DPRINTK("ENTER\n");
+
+	spin_lock_irqsave(&ap->host_set->lock, flags);
+	qc = ata_qc_from_tag(ap, ap->active_tag);
+	if (qc) {
+		assert(qc->scsicmd == cmd);
+		qc->flags |= ATA_QCFLAG_EH_SCHEDULED;
+		qc->err_mask |= AC_ERR_TIMEOUT;
+		ret = EH_NOT_HANDLED;
+	}
+	spin_unlock_irqrestore(&ap->host_set->lock, flags);
+
+	DPRINTK("EXIT, ret=%d\n", ret);
+	return ret;
+}
+
 /**
  *	ata_scsi_error - SCSI layer error handler callback
  *	@host: SCSI host on which error occurred
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 5c70a57f93e..c1e198655bb 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -509,6 +509,7 @@ 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);
 extern int ata_scsi_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *));
+extern enum scsi_eh_timer_return ata_scsi_timed_out(struct scsi_cmnd *cmd);
 extern int ata_scsi_error(struct Scsi_Host *host);
 extern void ata_eh_qc_complete(struct ata_queued_cmd *qc);
 extern void ata_eh_qc_retry(struct ata_queued_cmd *qc);
-- 
cgit v1.2.3


From 35daeb8f9b41fd13180e8a6f8bec9fc5268938f9 Mon Sep 17 00:00:00 2001
From: Tejun Heo <htejun@gmail.com>
Date: Fri, 10 Feb 2006 15:10:48 +0900
Subject: [PATCH] libata: use ata_scsi_timed_out()

Make all libata low level drivers use ata_scsi_timed_out().

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
---
 drivers/scsi/ahci.c         | 1 +
 drivers/scsi/ata_piix.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 +
 15 files changed, 15 insertions(+)

diff --git a/drivers/scsi/ahci.c b/drivers/scsi/ahci.c
index c840d5ec12a..c67189a4e0b 100644
--- a/drivers/scsi/ahci.c
+++ b/drivers/scsi/ahci.c
@@ -206,6 +206,7 @@ static struct scsi_host_template ahci_sht = {
 	.name			= DRV_NAME,
 	.ioctl			= ata_scsi_ioctl,
 	.queuecommand		= ata_scsi_queuecmd,
+	.eh_timed_out		= ata_scsi_timed_out,
 	.eh_strategy_handler	= ata_scsi_error,
 	.can_queue		= ATA_DEF_QUEUE,
 	.this_id		= ATA_SHT_THIS_ID,
diff --git a/drivers/scsi/ata_piix.c b/drivers/scsi/ata_piix.c
index 49cc4209fe1..4933ba28488 100644
--- a/drivers/scsi/ata_piix.c
+++ b/drivers/scsi/ata_piix.c
@@ -180,6 +180,7 @@ static struct scsi_host_template piix_sht = {
 	.name			= DRV_NAME,
 	.ioctl			= ata_scsi_ioctl,
 	.queuecommand		= ata_scsi_queuecmd,
+	.eh_timed_out		= ata_scsi_timed_out,
 	.eh_strategy_handler	= ata_scsi_error,
 	.can_queue		= ATA_DEF_QUEUE,
 	.this_id		= ATA_SHT_THIS_ID,
diff --git a/drivers/scsi/pdc_adma.c b/drivers/scsi/pdc_adma.c
index 3a6bf58dc37..d0ad3ebe968 100644
--- a/drivers/scsi/pdc_adma.c
+++ b/drivers/scsi/pdc_adma.c
@@ -143,6 +143,7 @@ static struct scsi_host_template adma_ata_sht = {
 	.name			= DRV_NAME,
 	.ioctl			= ata_scsi_ioctl,
 	.queuecommand		= ata_scsi_queuecmd,
+	.eh_timed_out		= ata_scsi_timed_out,
 	.eh_strategy_handler	= ata_scsi_error,
 	.can_queue		= ATA_DEF_QUEUE,
 	.this_id		= ATA_SHT_THIS_ID,
diff --git a/drivers/scsi/sata_mv.c b/drivers/scsi/sata_mv.c
index 3e916327ae3..1db05f23f12 100644
--- a/drivers/scsi/sata_mv.c
+++ b/drivers/scsi/sata_mv.c
@@ -378,6 +378,7 @@ static struct scsi_host_template mv_sht = {
 	.name			= DRV_NAME,
 	.ioctl			= ata_scsi_ioctl,
 	.queuecommand		= ata_scsi_queuecmd,
+	.eh_timed_out		= ata_scsi_timed_out,
 	.eh_strategy_handler	= ata_scsi_error,
 	.can_queue		= MV_USE_Q_DEPTH,
 	.this_id		= ATA_SHT_THIS_ID,
diff --git a/drivers/scsi/sata_nv.c b/drivers/scsi/sata_nv.c
index bbbb55eeb73..cdfeb9aa600 100644
--- a/drivers/scsi/sata_nv.c
+++ b/drivers/scsi/sata_nv.c
@@ -229,6 +229,7 @@ static struct scsi_host_template nv_sht = {
 	.name			= DRV_NAME,
 	.ioctl			= ata_scsi_ioctl,
 	.queuecommand		= ata_scsi_queuecmd,
+	.eh_timed_out		= ata_scsi_timed_out,
 	.eh_strategy_handler	= ata_scsi_error,
 	.can_queue		= ATA_DEF_QUEUE,
 	.this_id		= ATA_SHT_THIS_ID,
diff --git a/drivers/scsi/sata_promise.c b/drivers/scsi/sata_promise.c
index 0950a8e4581..5d4ed54d945 100644
--- a/drivers/scsi/sata_promise.c
+++ b/drivers/scsi/sata_promise.c
@@ -111,6 +111,7 @@ static struct scsi_host_template pdc_ata_sht = {
 	.name			= DRV_NAME,
 	.ioctl			= ata_scsi_ioctl,
 	.queuecommand		= ata_scsi_queuecmd,
+	.eh_timed_out		= ata_scsi_timed_out,
 	.eh_strategy_handler	= ata_scsi_error,
 	.can_queue		= ATA_DEF_QUEUE,
 	.this_id		= ATA_SHT_THIS_ID,
diff --git a/drivers/scsi/sata_qstor.c b/drivers/scsi/sata_qstor.c
index 2afbeb77f6f..82c3df7048e 100644
--- a/drivers/scsi/sata_qstor.c
+++ b/drivers/scsi/sata_qstor.c
@@ -132,6 +132,7 @@ static struct scsi_host_template qs_ata_sht = {
 	.name			= DRV_NAME,
 	.ioctl			= ata_scsi_ioctl,
 	.queuecommand		= ata_scsi_queuecmd,
+	.eh_timed_out		= ata_scsi_timed_out,
 	.eh_strategy_handler	= ata_scsi_error,
 	.can_queue		= ATA_DEF_QUEUE,
 	.this_id		= ATA_SHT_THIS_ID,
diff --git a/drivers/scsi/sata_sil.c b/drivers/scsi/sata_sil.c
index 17f74d3c10e..f40f25edbb1 100644
--- a/drivers/scsi/sata_sil.c
+++ b/drivers/scsi/sata_sil.c
@@ -135,6 +135,7 @@ static struct scsi_host_template sil_sht = {
 	.name			= DRV_NAME,
 	.ioctl			= ata_scsi_ioctl,
 	.queuecommand		= ata_scsi_queuecmd,
+	.eh_timed_out		= ata_scsi_timed_out,
 	.eh_strategy_handler	= ata_scsi_error,
 	.can_queue		= ATA_DEF_QUEUE,
 	.this_id		= ATA_SHT_THIS_ID,
diff --git a/drivers/scsi/sata_sil24.c b/drivers/scsi/sata_sil24.c
index 7222fc7ff3f..f4742ad3c96 100644
--- a/drivers/scsi/sata_sil24.c
+++ b/drivers/scsi/sata_sil24.c
@@ -280,6 +280,7 @@ static struct scsi_host_template sil24_sht = {
 	.name			= DRV_NAME,
 	.ioctl			= ata_scsi_ioctl,
 	.queuecommand		= ata_scsi_queuecmd,
+	.eh_timed_out		= ata_scsi_timed_out,
 	.eh_strategy_handler	= ata_scsi_error,
 	.can_queue		= ATA_DEF_QUEUE,
 	.this_id		= ATA_SHT_THIS_ID,
diff --git a/drivers/scsi/sata_sis.c b/drivers/scsi/sata_sis.c
index 2df8c5632ac..2f181571570 100644
--- a/drivers/scsi/sata_sis.c
+++ b/drivers/scsi/sata_sis.c
@@ -87,6 +87,7 @@ static struct scsi_host_template sis_sht = {
 	.name			= DRV_NAME,
 	.ioctl			= ata_scsi_ioctl,
 	.queuecommand		= ata_scsi_queuecmd,
+	.eh_timed_out		= ata_scsi_timed_out,
 	.eh_strategy_handler	= ata_scsi_error,
 	.can_queue		= ATA_DEF_QUEUE,
 	.this_id		= ATA_SHT_THIS_ID,
diff --git a/drivers/scsi/sata_svw.c b/drivers/scsi/sata_svw.c
index d8472563fde..f369c3003ad 100644
--- a/drivers/scsi/sata_svw.c
+++ b/drivers/scsi/sata_svw.c
@@ -288,6 +288,7 @@ static struct scsi_host_template k2_sata_sht = {
 	.name			= DRV_NAME,
 	.ioctl			= ata_scsi_ioctl,
 	.queuecommand		= ata_scsi_queuecmd,
+	.eh_timed_out		= ata_scsi_timed_out,
 	.eh_strategy_handler	= ata_scsi_error,
 	.can_queue		= ATA_DEF_QUEUE,
 	.this_id		= ATA_SHT_THIS_ID,
diff --git a/drivers/scsi/sata_sx4.c b/drivers/scsi/sata_sx4.c
index 9f992fbcf2e..3319f03b61a 100644
--- a/drivers/scsi/sata_sx4.c
+++ b/drivers/scsi/sata_sx4.c
@@ -182,6 +182,7 @@ static struct scsi_host_template pdc_sata_sht = {
 	.name			= DRV_NAME,
 	.ioctl			= ata_scsi_ioctl,
 	.queuecommand		= ata_scsi_queuecmd,
+	.eh_timed_out		= ata_scsi_timed_out,
 	.eh_strategy_handler	= ata_scsi_error,
 	.can_queue		= ATA_DEF_QUEUE,
 	.this_id		= ATA_SHT_THIS_ID,
diff --git a/drivers/scsi/sata_uli.c b/drivers/scsi/sata_uli.c
index 9635ca70097..c500f249090 100644
--- a/drivers/scsi/sata_uli.c
+++ b/drivers/scsi/sata_uli.c
@@ -75,6 +75,7 @@ static struct scsi_host_template uli_sht = {
 	.name			= DRV_NAME,
 	.ioctl			= ata_scsi_ioctl,
 	.queuecommand		= ata_scsi_queuecmd,
+	.eh_timed_out		= ata_scsi_timed_out,
 	.eh_strategy_handler	= ata_scsi_error,
 	.can_queue		= ATA_DEF_QUEUE,
 	.this_id		= ATA_SHT_THIS_ID,
diff --git a/drivers/scsi/sata_via.c b/drivers/scsi/sata_via.c
index 6d5b0a794cf..2e20887dc88 100644
--- a/drivers/scsi/sata_via.c
+++ b/drivers/scsi/sata_via.c
@@ -94,6 +94,7 @@ static struct scsi_host_template svia_sht = {
 	.name			= DRV_NAME,
 	.ioctl			= ata_scsi_ioctl,
 	.queuecommand		= ata_scsi_queuecmd,
+	.eh_timed_out		= ata_scsi_timed_out,
 	.eh_strategy_handler	= ata_scsi_error,
 	.can_queue		= ATA_DEF_QUEUE,
 	.this_id		= ATA_SHT_THIS_ID,
diff --git a/drivers/scsi/sata_vsc.c b/drivers/scsi/sata_vsc.c
index 2e2c3b7acb0..cf1f8a61bda 100644
--- a/drivers/scsi/sata_vsc.c
+++ b/drivers/scsi/sata_vsc.c
@@ -223,6 +223,7 @@ static struct scsi_host_template vsc_sata_sht = {
 	.name			= DRV_NAME,
 	.ioctl			= ata_scsi_ioctl,
 	.queuecommand		= ata_scsi_queuecmd,
+	.eh_timed_out		= ata_scsi_timed_out,
 	.eh_strategy_handler	= ata_scsi_error,
 	.can_queue		= ATA_DEF_QUEUE,
 	.this_id		= ATA_SHT_THIS_ID,
-- 
cgit v1.2.3


From f63790201521ccadb63673ff121dac46ab300cf0 Mon Sep 17 00:00:00 2001
From: Tejun Heo <htejun@gmail.com>
Date: Fri, 10 Feb 2006 15:10:48 +0900
Subject: [PATCH] libata: kill NULL qc handling from ->eng_timeout callbacks

->eng_timeout cannot be invoked with NULL qc anymore.  Add an
assertion in ata_scsi_error() and kill NULL qc handling from all
->eng_timeout callbacks.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
---
 drivers/scsi/ahci.c         | 12 +++---------
 drivers/scsi/libata-core.c  | 12 +-----------
 drivers/scsi/libata-scsi.c  |  1 +
 drivers/scsi/sata_mv.c      |  9 ++-------
 drivers/scsi/sata_promise.c |  9 +--------
 drivers/scsi/sata_sil24.c   |  5 -----
 drivers/scsi/sata_sx4.c     |  9 +--------
 7 files changed, 9 insertions(+), 48 deletions(-)

diff --git a/drivers/scsi/ahci.c b/drivers/scsi/ahci.c
index c67189a4e0b..fa01894fc41 100644
--- a/drivers/scsi/ahci.c
+++ b/drivers/scsi/ahci.c
@@ -677,19 +677,13 @@ static void ahci_eng_timeout(struct ata_port *ap)
 
 	spin_lock_irqsave(&host_set->lock, flags);
 
+	ahci_restart_port(ap, readl(port_mmio + PORT_IRQ_STAT));
 	qc = ata_qc_from_tag(ap, ap->active_tag);
-	if (!qc) {
-		printk(KERN_ERR "ata%u: BUG: timeout without command\n",
-		       ap->id);
-	} else {
-		ahci_restart_port(ap, readl(port_mmio + PORT_IRQ_STAT));
-		qc->err_mask |= AC_ERR_TIMEOUT;
-	}
+	qc->err_mask |= AC_ERR_TIMEOUT;
 
 	spin_unlock_irqrestore(&host_set->lock, flags);
 
-	if (qc)
-		ata_eh_qc_complete(qc);
+	ata_eh_qc_complete(qc);
 }
 
 static inline int ahci_host_intr(struct ata_port *ap, struct ata_queued_cmd *qc)
diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index d53e0bce2be..b938c7a3766 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -3524,20 +3524,10 @@ static void ata_qc_timeout(struct ata_queued_cmd *qc)
 
 void ata_eng_timeout(struct ata_port *ap)
 {
-	struct ata_queued_cmd *qc;
-
 	DPRINTK("ENTER\n");
 
-	qc = ata_qc_from_tag(ap, ap->active_tag);
-	if (qc)
-		ata_qc_timeout(qc);
-	else {
-		printk(KERN_ERR "ata%u: BUG: timeout without command\n",
-		       ap->id);
-		goto out;
-	}
+	ata_qc_timeout(ata_qc_from_tag(ap, ap->active_tag));
 
-out:
 	DPRINTK("EXIT\n");
 }
 
diff --git a/drivers/scsi/libata-scsi.c b/drivers/scsi/libata-scsi.c
index d67cc2fb569..9d67c676833 100644
--- a/drivers/scsi/libata-scsi.c
+++ b/drivers/scsi/libata-scsi.c
@@ -782,6 +782,7 @@ int ata_scsi_error(struct Scsi_Host *host)
 	spin_lock_irqsave(&ap->host_set->lock, flags);
 	assert(!(ap->flags & ATA_FLAG_IN_EH));
 	ap->flags |= ATA_FLAG_IN_EH;
+	assert(ata_qc_from_tag(ap, ap->active_tag) != NULL);
 	spin_unlock_irqrestore(&ap->host_set->lock, flags);
 
 	ap->ops->eng_timeout(ap);
diff --git a/drivers/scsi/sata_mv.c b/drivers/scsi/sata_mv.c
index 1db05f23f12..6c80527ddd2 100644
--- a/drivers/scsi/sata_mv.c
+++ b/drivers/scsi/sata_mv.c
@@ -2027,13 +2027,8 @@ static void mv_eng_timeout(struct ata_port *ap)
 	mv_err_intr(ap);
 	mv_stop_and_reset(ap);
 
-	if (!qc) {
-		printk(KERN_ERR "ata%u: BUG: timeout without command\n",
-		       ap->id);
-	} else {
-		qc->err_mask |= AC_ERR_TIMEOUT;
-		ata_eh_qc_complete(qc);
-	}
+	qc->err_mask |= AC_ERR_TIMEOUT;
+	ata_eh_qc_complete(qc);
 }
 
 /**
diff --git a/drivers/scsi/sata_promise.c b/drivers/scsi/sata_promise.c
index 5d4ed54d945..c9dfd937091 100644
--- a/drivers/scsi/sata_promise.c
+++ b/drivers/scsi/sata_promise.c
@@ -432,11 +432,6 @@ static void pdc_eng_timeout(struct ata_port *ap)
 	spin_lock_irqsave(&host_set->lock, flags);
 
 	qc = ata_qc_from_tag(ap, ap->active_tag);
-	if (!qc) {
-		printk(KERN_ERR "ata%u: BUG: timeout without command\n",
-		       ap->id);
-		goto out;
-	}
 
 	switch (qc->tf.protocol) {
 	case ATA_PROT_DMA:
@@ -456,10 +451,8 @@ static void pdc_eng_timeout(struct ata_port *ap)
 		break;
 	}
 
-out:
 	spin_unlock_irqrestore(&host_set->lock, flags);
-	if (qc)
-		ata_eh_qc_complete(qc);
+	ata_eh_qc_complete(qc);
 	DPRINTK("EXIT\n");
 }
 
diff --git a/drivers/scsi/sata_sil24.c b/drivers/scsi/sata_sil24.c
index f4742ad3c96..962396b36f6 100644
--- a/drivers/scsi/sata_sil24.c
+++ b/drivers/scsi/sata_sil24.c
@@ -639,11 +639,6 @@ static void sil24_eng_timeout(struct ata_port *ap)
 	struct ata_queued_cmd *qc;
 
 	qc = ata_qc_from_tag(ap, ap->active_tag);
-	if (!qc) {
-		printk(KERN_ERR "ata%u: BUG: timeout without command\n",
-		       ap->id);
-		return;
-	}
 
 	printk(KERN_ERR "ata%u: command timeout\n", ap->id);
 	qc->err_mask |= AC_ERR_TIMEOUT;
diff --git a/drivers/scsi/sata_sx4.c b/drivers/scsi/sata_sx4.c
index 3319f03b61a..212cff4fe5f 100644
--- a/drivers/scsi/sata_sx4.c
+++ b/drivers/scsi/sata_sx4.c
@@ -867,11 +867,6 @@ static void pdc_eng_timeout(struct ata_port *ap)
 	spin_lock_irqsave(&host_set->lock, flags);
 
 	qc = ata_qc_from_tag(ap, ap->active_tag);
-	if (!qc) {
-		printk(KERN_ERR "ata%u: BUG: timeout without command\n",
-		       ap->id);
-		goto out;
-	}
 
 	switch (qc->tf.protocol) {
 	case ATA_PROT_DMA:
@@ -890,10 +885,8 @@ static void pdc_eng_timeout(struct ata_port *ap)
 		break;
 	}
 
-out:
 	spin_unlock_irqrestore(&host_set->lock, flags);
-	if (qc)
-		ata_eh_qc_complete(qc);
+	ata_eh_qc_complete(qc);
 	DPRINTK("EXIT\n");
 }
 
-- 
cgit v1.2.3


From cc9278ed5e992122a654a3f762561ee5e013810f Mon Sep 17 00:00:00 2001
From: Tejun Heo <htejun@gmail.com>
Date: Fri, 10 Feb 2006 17:25:47 +0900
Subject: [PATCH] ahci: separate out ahci_fill_cmd_slot()

Separate out ahci_fill_cmd_slot() from ahci_qc_prep().
ahci_fill_cmd_slot() can later be used to issue non-standard commands.
(e.g. softreset)

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
---
 drivers/scsi/ahci.c | 44 +++++++++++++++++++++++---------------------
 1 file changed, 23 insertions(+), 21 deletions(-)

diff --git a/drivers/scsi/ahci.c b/drivers/scsi/ahci.c
index fa01894fc41..98ce6bb62ff 100644
--- a/drivers/scsi/ahci.c
+++ b/drivers/scsi/ahci.c
@@ -507,6 +507,15 @@ static unsigned int ahci_dev_classify(struct ata_port *ap)
 	return ata_dev_classify(&tf);
 }
 
+static void ahci_fill_cmd_slot(struct ata_port *ap, u32 opts)
+{
+	struct ahci_port_priv *pp = ap->private_data;
+	pp->cmd_slot[0].opts = cpu_to_le32(opts);
+	pp->cmd_slot[0].status = 0;
+	pp->cmd_slot[0].tbl_addr = cpu_to_le32(pp->cmd_tbl_dma & 0xffffffff);
+	pp->cmd_slot[0].tbl_addr_hi = cpu_to_le32((pp->cmd_tbl_dma >> 16) >> 16);
+}
+
 static void ahci_phy_reset(struct ata_port *ap)
 {
 	void __iomem *port_mmio = (void __iomem *) ap->ioaddr.cmd_addr;
@@ -585,42 +594,35 @@ static void ahci_qc_prep(struct ata_queued_cmd *qc)
 {
 	struct ata_port *ap = qc->ap;
 	struct ahci_port_priv *pp = ap->private_data;
+	int is_atapi = is_atapi_taskfile(&qc->tf);
 	u32 opts;
 	const u32 cmd_fis_len = 5; /* five dwords */
 	unsigned int n_elem;
 
-	/*
-	 * Fill in command slot information (currently only one slot,
-	 * slot 0, is currently since we don't do queueing)
-	 */
-
-	opts = cmd_fis_len;
-	if (qc->tf.flags & ATA_TFLAG_WRITE)
-		opts |= AHCI_CMD_WRITE;
-	if (is_atapi_taskfile(&qc->tf))
-		opts |= AHCI_CMD_ATAPI;
-
-	pp->cmd_slot[0].opts = cpu_to_le32(opts);
-	pp->cmd_slot[0].status = 0;
-	pp->cmd_slot[0].tbl_addr = cpu_to_le32(pp->cmd_tbl_dma & 0xffffffff);
-	pp->cmd_slot[0].tbl_addr_hi = cpu_to_le32((pp->cmd_tbl_dma >> 16) >> 16);
-
 	/*
 	 * Fill in command table information.  First, the header,
 	 * a SATA Register - Host to Device command FIS.
 	 */
 	ata_tf_to_fis(&qc->tf, pp->cmd_tbl, 0);
-	if (opts & AHCI_CMD_ATAPI) {
+	if (is_atapi) {
 		memset(pp->cmd_tbl + AHCI_CMD_TBL_CDB, 0, 32);
 		memcpy(pp->cmd_tbl + AHCI_CMD_TBL_CDB, qc->cdb, ap->cdb_len);
 	}
 
-	if (!(qc->flags & ATA_QCFLAG_DMAMAP))
-		return;
+	n_elem = 0;
+	if (qc->flags & ATA_QCFLAG_DMAMAP)
+		n_elem = ahci_fill_sg(qc);
 
-	n_elem = ahci_fill_sg(qc);
+	/*
+	 * Fill in command slot information.
+	 */
+	opts = cmd_fis_len | n_elem << 16;
+	if (qc->tf.flags & ATA_TFLAG_WRITE)
+		opts |= AHCI_CMD_WRITE;
+	if (is_atapi)
+		opts |= AHCI_CMD_ATAPI;
 
-	pp->cmd_slot[0].opts |= cpu_to_le32(n_elem << 16);
+	ahci_fill_cmd_slot(ap, opts);
 }
 
 static void ahci_restart_port(struct ata_port *ap, u32 irq_stat)
-- 
cgit v1.2.3