[libata irq-pio] reorganize ata_pio_sector() and __atapi_pio_bytes()

   - move some code out of the kmap_atomic() / kunmap_atomic() zone
   - remove the redundant "do_write = (qc->tf.flags & ATA_TFLAG_WRITE);"

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

drivers/scsi/libata-core.c

@@ -2763,22 +2763,21 @@ static void ata_pio_sector(struct ata_queued_cmd *qc)
 	local_irq_save(flags);
 	buf = kmap_atomic(page, KM_IRQ0) + offset;
 
-	qc->cursect++;
-	qc->cursg_ofs++;
-
-	if ((qc->cursg_ofs * ATA_SECT_SIZE) == (&sg[qc->cursg])->length) {
-		qc->cursg++;
-		qc->cursg_ofs = 0;
-	}
-
 	DPRINTK("data %s\n", qc->tf.flags & ATA_TFLAG_WRITE ? "write" : "read");
 
 	/* do the actual data transfer */
-	do_write = (qc->tf.flags & ATA_TFLAG_WRITE);
 	ata_data_xfer(ap, buf, ATA_SECT_SIZE, do_write);
 
 	kunmap_atomic(buf - offset, KM_IRQ0);
 	local_irq_restore(flags);
+
+	qc->cursect++;
+	qc->cursg_ofs++;
+
+	if ((qc->cursg_ofs * ATA_SECT_SIZE) == (&sg[qc->cursg])->length) {
+		qc->cursg++;
+		qc->cursg_ofs = 0;
+	}
 }
 
 /**
@@ -2956,6 +2955,14 @@ static void __atapi_pio_bytes(struct ata_queued_cmd *qc, unsigned int bytes)
 	local_irq_save(flags);
 	buf = kmap_atomic(page, KM_IRQ0) + offset;
 
+	DPRINTK("data %s\n", qc->tf.flags & ATA_TFLAG_WRITE ? "write" : "read");
+
+	/* do the actual data transfer */
+	ata_data_xfer(ap, buf, count, do_write);
+
+	kunmap_atomic(buf - offset, KM_IRQ0);
+	local_irq_restore(flags);
+
 	bytes -= count;
 	qc->curbytes += count;
 	qc->cursg_ofs += count;
@@ -2965,14 +2972,6 @@ static void __atapi_pio_bytes(struct ata_queued_cmd *qc, unsigned int bytes)
 		qc->cursg_ofs = 0;
 	}
 
-	DPRINTK("data %s\n", qc->tf.flags & ATA_TFLAG_WRITE ? "write" : "read");
-
-	/* do the actual data transfer */
-	ata_data_xfer(ap, buf, count, do_write);
-
-	kunmap_atomic(buf - offset, KM_IRQ0);
-	local_irq_restore(flags);
-
 	if (bytes)
 		goto next_sg;
 }