[PATCH] libata: EH / pio tasks synchronization
This patch makes sure that pio tasks are flushed before proceeding
with EH.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index 249e67f..9a785cf 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -1074,19 +1074,66 @@
static inline void
ata_queue_packet_task(struct ata_port *ap)
{
- queue_work(ata_wq, &ap->packet_task);
+ if (!(ap->flags & ATA_FLAG_FLUSH_PIO_TASK))
+ queue_work(ata_wq, &ap->packet_task);
}
static inline void
ata_queue_pio_task(struct ata_port *ap)
{
- queue_work(ata_wq, &ap->pio_task);
+ if (!(ap->flags & ATA_FLAG_FLUSH_PIO_TASK))
+ queue_work(ata_wq, &ap->pio_task);
}
static inline void
ata_queue_delayed_pio_task(struct ata_port *ap, unsigned long delay)
{
- queue_delayed_work(ata_wq, &ap->pio_task, delay);
+ if (!(ap->flags & ATA_FLAG_FLUSH_PIO_TASK))
+ queue_delayed_work(ata_wq, &ap->pio_task, delay);
+}
+
+/**
+ * ata_flush_pio_tasks - Flush pio_task and packet_task
+ * @ap: the target ata_port
+ *
+ * After this function completes, pio_task and packet_task are
+ * guranteed not to be running or scheduled.
+ *
+ * LOCKING:
+ * Kernel thread context (may sleep)
+ */
+
+static void ata_flush_pio_tasks(struct ata_port *ap)
+{
+ int tmp = 0;
+ unsigned long flags;
+
+ DPRINTK("ENTER\n");
+
+ spin_lock_irqsave(&ap->host_set->lock, flags);
+ ap->flags |= ATA_FLAG_FLUSH_PIO_TASK;
+ spin_unlock_irqrestore(&ap->host_set->lock, flags);
+
+ DPRINTK("flush #1\n");
+ flush_workqueue(ata_wq);
+
+ /*
+ * At this point, if a task is running, it's guaranteed to see
+ * the FLUSH flag; thus, it will never queue pio tasks again.
+ * Cancel and flush.
+ */
+ tmp |= cancel_delayed_work(&ap->pio_task);
+ tmp |= cancel_delayed_work(&ap->packet_task);
+ if (!tmp) {
+ DPRINTK("flush #2\n");
+ flush_workqueue(ata_wq);
+ }
+
+ spin_lock_irqsave(&ap->host_set->lock, flags);
+ ap->flags &= ~ATA_FLAG_FLUSH_PIO_TASK;
+ spin_unlock_irqrestore(&ap->host_set->lock, flags);
+
+ DPRINTK("EXIT\n");
}
void ata_qc_complete_internal(struct ata_queued_cmd *qc)
@@ -3767,6 +3814,9 @@
DPRINTK("ENTER\n");
+ ata_flush_pio_tasks(ap);
+ ap->hsm_task_state = HSM_ST_IDLE;
+
spin_lock_irqsave(&host_set->lock, flags);
switch (qc->tf.protocol) {