ide-tape: change IDE_AFLAG_IGNORE_DSC non-atomically

There are two sites where the flag is being changed: ide_retry_pc
and idetape_do_request. Both codepaths are protected by hwif->busy
(ide_lock_port) and therefore we shouldn't need the atomic accesses.

Spotted-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

2 files changed, 8 insertions, 6 deletions

diff --git a/drivers/ide/ide-atapi.c b/drivers/ide/ide-atapi.c
index afe5a4323879..fbcb8513a4c8 100644
--- a/drivers/ide/ide-atapi.c
+++ b/drivers/ide/ide-atapi.c
@@ -258,7 +258,7 @@ void ide_retry_pc(ide_drive_t *drive)
         pc->req_xfer = sense_rq->data_len;
 
         if (drive->media == ide_tape)
-                set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags);
+                drive->atapi_flags |= IDE_AFLAG_IGNORE_DSC;
 
         if (ide_queue_sense_rq(drive, pc))
                 ide_complete_rq(drive, -EIO, blk_rq_bytes(drive->hwif->rq));
diff --git a/drivers/ide/ide-tape.c b/drivers/ide/ide-tape.c
index 203bbeac182f..f1d3c7b2a2b5 100644
--- a/drivers/ide/ide-tape.c
+++ b/drivers/ide/ide-tape.c
@@ -656,15 +656,15 @@ static ide_startstop_t idetape_do_request(ide_drive_t *drive,
 
         if ((drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) == 0 &&
             (rq->cmd[13] & REQ_IDETAPE_PC2) == 0)
-                set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags);
+                drive->atapi_flags |= IDE_AFLAG_IGNORE_DSC;
 
         if (drive->dev_flags & IDE_DFLAG_POST_RESET) {
-                set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags);
+                drive->atapi_flags |= IDE_AFLAG_IGNORE_DSC;
                 drive->dev_flags &= ~IDE_DFLAG_POST_RESET;
         }
 
-        if (!test_and_clear_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags) &&
-            (stat & ATA_DSC) == 0) {
+        if (!(drive->atapi_flags & IDE_AFLAG_IGNORE_DSC) &&
+            !(stat & ATA_DSC)) {
                 if (postponed_rq == NULL) {
                         tape->dsc_polling_start = jiffies;
                         tape->dsc_poll_freq = tape->best_dsc_rw_freq;
@@ -684,7 +684,9 @@ static ide_startstop_t idetape_do_request(ide_drive_t *drive,
                         tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW;
                 idetape_postpone_request(drive);
                 return ide_stopped;
-        }
+        } else
+                drive->atapi_flags &= ~IDE_AFLAG_IGNORE_DSC;
+
         if (rq->cmd[13] & REQ_IDETAPE_READ) {
                 pc = &tape->queued_pc;
                 ide_tape_create_rw_cmd(tape, pc, rq, READ_6);