[PATCH] libata: err_mask misc fix

  1. ata_pio_complete():
     It seems unnecessary to wait for the clearing of the DRQ bit.
     (Waiting for BSY=0 should be enough.
     ata_ok() also checks the correctness of the status bits later.)

  2. ata_pio_block():
     - added error checking, before transfering data.
     - minor comments fix

Signed-off-by: Albert Lee <albertcc@tw.ibm.com>

============
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>

1 files changed, 13 insertions, 5 deletions

diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index b3aedb03346..e4c400756b2 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -2865,11 +2865,11 @@ static int ata_pio_complete (struct ata_port *ap)
          * msecs, then chk-status again.  If still busy, fall back to
          * HSM_ST_POLL state.
          */
-        drv_stat = ata_busy_wait(ap, ATA_BUSY | ATA_DRQ, 10);
-        if (drv_stat & (ATA_BUSY | ATA_DRQ)) {
+        drv_stat = ata_busy_wait(ap, ATA_BUSY, 10);
+        if (drv_stat & ATA_BUSY) {
                 msleep(2);
-                drv_stat = ata_busy_wait(ap, ATA_BUSY | ATA_DRQ, 10);
-                if (drv_stat & (ATA_BUSY | ATA_DRQ)) {
+                drv_stat = ata_busy_wait(ap, ATA_BUSY, 10);
+                if (drv_stat & ATA_BUSY) {
                         ap->hsm_task_state = HSM_ST_LAST_POLL;
                         ap->pio_task_timeout = jiffies + ATA_TMOUT_PIO;
                         return 0;
@@ -3236,8 +3236,16 @@ static void ata_pio_block(struct ata_port *ap)
         qc = ata_qc_from_tag(ap, ap->active_tag);
         assert(qc != NULL);
 
+        /* check error */
+        if (status & (ATA_ERR | ATA_DF)) {
+                qc->err_mask |= AC_ERR_DEV;
+                ap->hsm_task_state = HSM_ST_ERR;
+                return;
+        }
+
+        /* transfer data if any */
         if (is_atapi_taskfile(&qc->tf)) {
-                /* no more data to transfer or unsupported ATAPI command */
+                /* DRQ=0 means no more data to transfer */
                 if ((status & ATA_DRQ) == 0) {
                         ap->hsm_task_state = HSM_ST_LAST;
                         return;