ide-disk: use do_rw_taskfile() (take 2)

* Add IDE_TFLAG_DMA_PIO_FALLBACK taskfile flag to indicate the need
  to skip loading taskfile registers in do_rw_taskfile().

* Export do_rw_taskfile().

* Convert __ide_do_rw_disk() to use do_rw_taskfile().

* Unexport ide_tf_load().

* Unexport {pre_task_out,task_in}_intr() and make it static.

* Remove incorrect comment about do_rw_taskfile() from <linux/ide.h>.

There should be no functionality changes caused by this patch.

v2:
* Add missing blk_fs_request() check to task_dma_ok() (for VDMA).

Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

1 files changed, 10 insertions, 19 deletions

diff --git a/drivers/ide/ide-disk.c b/drivers/ide/ide-disk.c
index 97abc91db7d0..3d7127ba67a0 100644
--- a/drivers/ide/ide-disk.c
+++ b/drivers/ide/ide-disk.c
@@ -185,6 +185,7 @@ static ide_startstop_t __ide_do_rw_disk(ide_drive_t *drive, struct request *rq,
         u8 lba48                = (drive->addressing == 1) ? 1 : 0;
         ide_task_t              task;
         struct ide_taskfile     *tf = &task.tf;
+        ide_startstop_t         rc;
 
         if ((hwif->host_flags & IDE_HFLAG_NO_LBA48_DMA) && lba48 && dma) {
                 if (block + rq->nr_sectors > 1ULL << 28)
@@ -252,32 +253,22 @@ static ide_startstop_t __ide_do_rw_disk(ide_drive_t *drive, struct request *rq,
                 task.tf_flags |= IDE_TFLAG_WRITE;
 
         ide_tf_set_cmd(drive, &task, dma);
+        if (!dma)
+                hwif->data_phase = task.data_phase;
+        task.rq = rq;
 
-        ide_tf_load(drive, &task);
+        rc = do_rw_taskfile(drive, &task);
 
-        if (dma) {
-                if (!hwif->dma_setup(drive)) {
-                        hwif->dma_exec_cmd(drive, tf->command);
-                        hwif->dma_start(drive);
-                        return ide_started;
-                }
+        if (rc == ide_stopped && dma) {
                 /* fallback to PIO */
+                task.tf_flags |= IDE_TFLAG_DMA_PIO_FALLBACK;
                 ide_tf_set_cmd(drive, &task, 0);
+                hwif->data_phase = task.data_phase;
                 ide_init_sg_cmd(drive, rq);
+                rc = do_rw_taskfile(drive, &task);
         }
 
-        hwif->data_phase = task.data_phase;
-
-        if (rq_data_dir(rq) == READ) {
-                ide_execute_command(drive, tf->command, &task_in_intr,
-                                    WAIT_WORSTCASE, NULL);
-                return ide_started;
-        } else {
-                hwif->OUTBSYNC(drive, tf->command, IDE_COMMAND_REG);
-                ndelay(400);    /* FIXME */
-
-                return pre_task_out_intr(drive, rq);
-        }
+        return rc;
 }
 
 /*