[PATCH] libata irq-pio: cleanup ata_qc_issue_prot()

ata_qc_issue_prot():
    - cleanup and let the PIO data out case always go through the
ata_dataout_task() codepath.
      (Previously for PIO data out case, 2 code pathes were used
        - irq case goes through ata_data_out_task() codepath.
        - polling case jumps over the HSM_ST_FIRST state and goes to
HSM_ST and ata_pio_task() directly.)

  ata_dataout_task():
    - rearrange the queue_work() code to handle the PIO data out +
polling case.

Signed-off-by: Albert Lee <albertcc@tw.ibm.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>

1 files changed, 23 insertions, 23 deletions

diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index cf5a138cdde5..02a7a9eb464d 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -3407,24 +3407,24 @@ int ata_qc_issue_prot(struct ata_queued_cmd *qc)
 
                 ata_tf_to_host_nolock(ap, &qc->tf);
 
-                if (qc->tf.flags & ATA_TFLAG_POLLING) {
-                        /* polling PIO */
-                        ap->hsm_task_state = HSM_ST;
-                        queue_work(ata_wq, &ap->pio_task);
+                if (qc->tf.flags & ATA_TFLAG_WRITE) {
+                        /* PIO data out protocol */
+                        ap->hsm_task_state = HSM_ST_FIRST;
+                        queue_work(ata_wq, &ap->dataout_task);
+
+                        /* always send first data block using
+                         * the ata_dataout_task() codepath.
+                         */
                 } else {
-                        /* interrupt driven PIO */
-                        if (qc->tf.flags & ATA_TFLAG_WRITE) {
-                                /* PIO data out protocol */
-                                ap->hsm_task_state = HSM_ST_FIRST;
-                                queue_work(ata_wq, &ap->dataout_task);
-
-                                /* send first data block by polling */
-                        } else {
-                                /* PIO data in protocol */
-                                ap->hsm_task_state = HSM_ST;
-
-                                /* interrupt handler takes over from here */
-                        }
+                        /* PIO data in protocol */
+                        ap->hsm_task_state = HSM_ST;
+
+                        if (qc->tf.flags & ATA_TFLAG_POLLING)
+                                queue_work(ata_wq, &ap->pio_task);
+
+                        /* if polling, ata_pio_task() handles the rest.
+                         * otherwise, interrupt handler takes over from here.
+                         */
                 }
 
                 break;
@@ -4005,15 +4005,15 @@ static void ata_dataout_task(void *_data)
                 ap->hsm_task_state = HSM_ST;
                 ata_pio_sector(qc);
                 ata_altstatus(ap); /* flush */
-
-                /* interrupt handler takes over from here */
-        } else {
+        } else
                 /* send CDB */
                 atapi_send_cdb(ap, qc);
 
-                if (qc->tf.flags & ATA_TFLAG_POLLING)
-                        queue_work(ata_wq, &ap->pio_task);
-        }
+        /* if polling, ata_pio_task() handles the rest.
+         * otherwise, interrupt handler takes over from here.
+         */
+        if (qc->tf.flags & ATA_TFLAG_POLLING)
+                queue_work(ata_wq, &ap->pio_task);
 
         spin_unlock_irqrestore(&ap->host_set->lock, flags);