ide-atapi: accomodate transfer length calculation for ide-cd

... by factoring it out of ide_cd_do_request() into a helper, as suggested by
Bart.

There should be no functionality change resulting from this patch.

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
[bart: BLK_DEV_IDECD needs to select IDE_ATAPI now]
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

3 files changed, 17 insertions, 3 deletions

diff --git a/drivers/ide/Kconfig b/drivers/ide/Kconfig
index 937945e471df..4ee85fcf9aaf 100644
--- a/drivers/ide/Kconfig
+++ b/drivers/ide/Kconfig
@@ -137,6 +137,7 @@ config BLK_DEV_DELKIN
 
 config BLK_DEV_IDECD
         tristate "Include IDE/ATAPI CDROM support"
+        select IDE_ATAPI
         ---help---
           If you have a CD-ROM drive using the ATAPI protocol, say Y. ATAPI is
           a newer protocol used by IDE CD-ROM and TAPE drives, similar to the
diff --git a/drivers/ide/ide-atapi.c b/drivers/ide/ide-atapi.c
index 74273fdc8827..8884877bd2b5 100644
--- a/drivers/ide/ide-atapi.c
+++ b/drivers/ide/ide-atapi.c
@@ -252,6 +252,18 @@ int ide_scsi_expiry(ide_drive_t *drive)
 }
 EXPORT_SYMBOL_GPL(ide_scsi_expiry);
 
+int ide_cd_get_xferlen(struct request *rq)
+{
+        if (blk_fs_request(rq))
+                return 32768;
+        else if (blk_sense_request(rq) || blk_pc_request(rq) ||
+                         rq->cmd_type == REQ_TYPE_ATA_PC)
+                return rq->data_len;
+        else
+                return 0;
+}
+EXPORT_SYMBOL_GPL(ide_cd_get_xferlen);
+
 /*
  * This is the usual interrupt handler which will be called during a packet
  * command.  We will transfer some of the data (as requested by the drive)
@@ -551,7 +563,7 @@ ide_startstop_t ide_issue_pc(ide_drive_t *drive, unsigned int timeout,
         struct ide_atapi_pc *pc = drive->pc;
         ide_hwif_t *hwif = drive->hwif;
         u32 tf_flags;
-        u16 bcount = 0;
+        u16 bcount;
         u8 scsi = !!(drive->dev_flags & IDE_DFLAG_SCSI);
 
         /* We haven't transferred any data yet */
@@ -560,6 +572,7 @@ ide_startstop_t ide_issue_pc(ide_drive_t *drive, unsigned int timeout,
 
         if (dev_is_idecd(drive)) {
                 tf_flags = IDE_TFLAG_OUT_NSECT | IDE_TFLAG_OUT_LBAL;
+                bcount = ide_cd_get_xferlen(hwif->hwgroup->rq);
         } else if (scsi) {
                 tf_flags = 0;
                 bcount = min(pc->req_xfer, 63 * 1024);
diff --git a/drivers/ide/ide-cd.c b/drivers/ide/ide-cd.c
index 65e5513758b0..8d3c7714682e 100644
--- a/drivers/ide/ide-cd.c
+++ b/drivers/ide/ide-cd.c
@@ -1214,8 +1214,9 @@ static ide_startstop_t ide_cd_do_request(ide_drive_t *drive, struct request *rq,
                       __func__, rq->cmd[0], rq->cmd_type,
                       (unsigned long long)block);
 
+        xferlen = ide_cd_get_xferlen(rq);
+
         if (blk_fs_request(rq)) {
-                xferlen = 32768;
                 fn = cdrom_start_rw_cont;
 
                 if (cdrom_start_rw(drive, rq) == ide_stopped)
@@ -1225,7 +1226,6 @@ static ide_startstop_t ide_cd_do_request(ide_drive_t *drive, struct request *rq,
                         return ide_stopped;
         } else if (blk_sense_request(rq) || blk_pc_request(rq) ||
                    rq->cmd_type == REQ_TYPE_ATA_PC) {
-                xferlen = rq->data_len;
                 fn = cdrom_do_newpc_cont;
 
                 if (!rq->timeout)