From c6cf9e99d1de5ca6a08fb639bb73031ffe50d802 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Wed, 31 May 2006 18:27:27 +0900 Subject: [PATCH] [PATCH] libata: implement ata_eh_wait() Implement ata_eh_wait(). On return from this function, it's guaranteed that the EH which was pending or in progress when the function was called is complete - including the tailing part of SCSI EH. This will be used by hotplug and others to synchronize with EH. Signed-off-by: Tejun Heo --- drivers/scsi/libata-core.c | 1 + drivers/scsi/libata-eh.c | 38 ++++++++++++++++++++++++++++++++++++++ drivers/scsi/libata.h | 1 + include/linux/libata.h | 2 ++ 4 files changed, 42 insertions(+) diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c index 11df827e166f..66df895c9617 100644 --- a/drivers/scsi/libata-core.c +++ b/drivers/scsi/libata-core.c @@ -5189,6 +5189,7 @@ static void ata_host_init(struct ata_port *ap, struct Scsi_Host *host, INIT_WORK(&ap->port_task, NULL, NULL); INIT_LIST_HEAD(&ap->eh_done_q); + init_waitqueue_head(&ap->eh_wait_q); /* set cable type */ ap->cbl = ATA_CBL_NONE; diff --git a/drivers/scsi/libata-eh.c b/drivers/scsi/libata-eh.c index b88f492eab12..9173d8f2ce5d 100644 --- a/drivers/scsi/libata-eh.c +++ b/drivers/scsi/libata-eh.c @@ -237,6 +237,7 @@ void ata_scsi_error(struct Scsi_Host *host) ap->eh_context.i = ap->eh_info; memset(&ap->eh_info, 0, sizeof(ap->eh_info)); + ap->flags |= ATA_FLAG_EH_IN_PROGRESS; ap->flags &= ~ATA_FLAG_EH_PENDING; spin_unlock_irqrestore(hs_lock, flags); @@ -290,11 +291,48 @@ void ata_scsi_error(struct Scsi_Host *host) ata_port_printk(ap, KERN_INFO, "EH complete\n"); ap->flags &= ~ATA_FLAG_RECOVERED; + /* tell wait_eh that we're done */ + ap->flags &= ~ATA_FLAG_EH_IN_PROGRESS; + wake_up_all(&ap->eh_wait_q); + spin_unlock_irqrestore(hs_lock, flags); DPRINTK("EXIT\n"); } +/** + * ata_port_wait_eh - Wait for the currently pending EH to complete + * @ap: Port to wait EH for + * + * Wait until the currently pending EH is complete. + * + * LOCKING: + * Kernel thread context (may sleep). + */ +void ata_port_wait_eh(struct ata_port *ap) +{ + unsigned long flags; + DEFINE_WAIT(wait); + + retry: + spin_lock_irqsave(&ap->host_set->lock, flags); + + while (ap->flags & (ATA_FLAG_EH_PENDING | ATA_FLAG_EH_IN_PROGRESS)) { + prepare_to_wait(&ap->eh_wait_q, &wait, TASK_UNINTERRUPTIBLE); + spin_unlock_irqrestore(&ap->host_set->lock, flags); + schedule(); + spin_lock_irqsave(&ap->host_set->lock, flags); + } + + spin_unlock_irqrestore(&ap->host_set->lock, flags); + + /* make sure SCSI EH is complete */ + if (scsi_host_in_recovery(ap->host)) { + msleep(10); + goto retry; + } +} + /** * ata_qc_timeout - Handle timeout of queued command * @qc: Command that timed out diff --git a/drivers/scsi/libata.h b/drivers/scsi/libata.h index b76ad7d7062a..d56d9e1d73dc 100644 --- a/drivers/scsi/libata.h +++ b/drivers/scsi/libata.h @@ -103,6 +103,7 @@ extern void ata_schedule_scsi_eh(struct Scsi_Host *shost); /* libata-eh.c */ extern enum scsi_eh_timer_return ata_scsi_timed_out(struct scsi_cmnd *cmd); extern void ata_scsi_error(struct Scsi_Host *host); +extern void ata_port_wait_eh(struct ata_port *ap); extern void ata_qc_schedule_eh(struct ata_queued_cmd *qc); #endif /* __LIBATA_H__ */ diff --git a/include/linux/libata.h b/include/linux/libata.h index 3f9c65f1aafa..2eb5828839e4 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -157,6 +157,7 @@ enum { ATA_FLAG_FLUSH_PORT_TASK = (1 << 14), /* flush port task */ ATA_FLAG_EH_PENDING = (1 << 15), /* EH pending */ + ATA_FLAG_EH_IN_PROGRESS = (1 << 16), /* EH in progress */ ATA_FLAG_FROZEN = (1 << 17), /* port is frozen */ ATA_FLAG_RECOVERED = (1 << 18), /* recovery action performed */ @@ -490,6 +491,7 @@ struct ata_port { u32 msg_enable; struct list_head eh_done_q; + wait_queue_head_t eh_wait_q; void *private_data; -- 2.20.1