[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 <htejun@gmail.com>

1 files changed, 2 insertions, 0 deletions

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;