From ece180d1cfe5fa751eaa85bf796cf28b2150af15 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Mon, 3 Nov 2008 20:04:37 +0900 Subject: [PATCH] libata: perform port detach in EH ata_port_detach() first made sure EH saw ATA_PFLAG_UNLOADING and then assumed EH context belongs to it and performed detach operation itself. However, UNLOADING doesn't disable all of EH and this could lead to problems including triggering WARN_ON()'s in EH path. This patch makes port detach behave more like other EH actions such that ata_port_detach() requests EH to detach and waits for completion. Signed-off-by: Tejun Heo Signed-off-by: Jeff Garzik --- drivers/ata/libata-core.c | 23 ++++------------------- drivers/ata/libata-eh.c | 32 +++++++++++++++++++++++++++++++- include/linux/libata.h | 3 ++- 3 files changed, 37 insertions(+), 21 deletions(-) diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c index 1ecc3cb..837fb60 100644 --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -6107,8 +6107,6 @@ int ata_host_activate(struct ata_host *host, int irq, static void ata_port_detach(struct ata_port *ap) { unsigned long flags; - struct ata_link *link; - struct ata_device *dev; if (!ap->ops->error_handler) goto skip_eh; @@ -6116,28 +6114,15 @@ static void ata_port_detach(struct ata_port *ap) /* tell EH we're leaving & flush EH */ spin_lock_irqsave(ap->lock, flags); ap->pflags |= ATA_PFLAG_UNLOADING; + ata_port_schedule_eh(ap); spin_unlock_irqrestore(ap->lock, flags); + /* wait till EH commits suicide */ ata_port_wait_eh(ap); - /* EH is now guaranteed to see UNLOADING - EH context belongs - * to us. Restore SControl and disable all existing devices. - */ - ata_for_each_link(link, ap, PMP_FIRST) { - sata_scr_write(link, SCR_CONTROL, link->saved_scontrol & 0xff0); - ata_for_each_dev(dev, link, ALL) - ata_dev_disable(dev); - } - - /* 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->lock, flags); - ata_port_freeze(ap); /* won't be thawed */ - spin_unlock_irqrestore(ap->lock, flags); + /* it better be dead now */ + WARN_ON(!(ap->pflags & ATA_PFLAG_UNLOADED)); - ata_port_wait_eh(ap); cancel_rearming_delayed_work(&ap->hotplug_task); skip_eh: diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c index d673f37..8147a83 100644 --- a/drivers/ata/libata-eh.c +++ b/drivers/ata/libata-eh.c @@ -491,6 +491,31 @@ enum blk_eh_timer_return ata_scsi_timed_out(struct scsi_cmnd *cmd) return ret; } +static void ata_eh_unload(struct ata_port *ap) +{ + struct ata_link *link; + struct ata_device *dev; + unsigned long flags; + + /* Restore SControl IPM and SPD for the next driver and + * disable attached devices. + */ + ata_for_each_link(link, ap, PMP_FIRST) { + sata_scr_write(link, SCR_CONTROL, link->saved_scontrol & 0xff0); + ata_for_each_dev(dev, link, ALL) + ata_dev_disable(dev); + } + + /* freeze and set UNLOADED */ + spin_lock_irqsave(ap->lock, flags); + + ata_port_freeze(ap); /* won't be thawed */ + ap->pflags &= ~ATA_PFLAG_EH_PENDING; /* clear pending from freeze */ + ap->pflags |= ATA_PFLAG_UNLOADED; + + spin_unlock_irqrestore(ap->lock, flags); +} + /** * ata_scsi_error - SCSI layer error handler callback * @host: SCSI host on which error occurred @@ -618,8 +643,13 @@ void ata_scsi_error(struct Scsi_Host *host) /* invoke EH, skip if unloading or suspended */ if (!(ap->pflags & (ATA_PFLAG_UNLOADING | ATA_PFLAG_SUSPENDED))) ap->ops->error_handler(ap); - else + else { + /* if unloading, commence suicide */ + if ((ap->pflags & ATA_PFLAG_UNLOADING) && + !(ap->pflags & ATA_PFLAG_UNLOADED)) + ata_eh_unload(ap); ata_eh_finish(ap); + } /* process port suspend request */ ata_eh_handle_port_suspend(ap); diff --git a/include/linux/libata.h b/include/linux/libata.h index 3b2a0c6..3449de5 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -213,10 +213,11 @@ enum { ATA_PFLAG_FROZEN = (1 << 2), /* port is frozen */ ATA_PFLAG_RECOVERED = (1 << 3), /* recovery action performed */ ATA_PFLAG_LOADING = (1 << 4), /* boot/loading probe */ - ATA_PFLAG_UNLOADING = (1 << 5), /* module is unloading */ ATA_PFLAG_SCSI_HOTPLUG = (1 << 6), /* SCSI hotplug scheduled */ ATA_PFLAG_INITIALIZING = (1 << 7), /* being initialized, don't touch */ ATA_PFLAG_RESETTING = (1 << 8), /* reset in progress */ + ATA_PFLAG_UNLOADING = (1 << 9), /* driver is being unloaded */ + ATA_PFLAG_UNLOADED = (1 << 10), /* driver is unloaded */ ATA_PFLAG_SUSPENDED = (1 << 17), /* port is suspended (power) */ ATA_PFLAG_PM_PENDING = (1 << 18), /* PM operation pending */ -- 2.7.4