[PATCH 11/28] ata: add CONFIG_SATA_HOST=n version of ata_ncq_enabled()

[Bartlomiej Zolnierkiewicz]

When CONFIG_SATA_HOST=n there are no NCQ capable host drivers
built so it is safe to hardwire ata_ncq_enabled() to always
return zero.

Code size savings on m68k arch using atari_defconfig:

   text    data     bss     dec     hex filename
before:
  37820     572      40   38432    9620 drivers/ata/libata-core.o
  21040     105    4096   25241    6299 drivers/ata/libata-scsi.o
  17405      18       0   17423    440f drivers/ata/libata-eh.o
after:
  37582     572      40   38194    9532 drivers/ata/libata-core.o
  20702     105    4096   24903    6147 drivers/ata/libata-scsi.o
  17353      18       0   17371    43db drivers/ata/libata-eh.o

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx>
---
 include/linux/libata.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/include/linux/libata.h b/include/linux/libata.h
index 79953c6d769c..5b7bed18f56e 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -1633,8 +1633,12 @@ extern struct ata_device *ata_dev_next(struct ata_device *dev,
  */
 static inline int ata_ncq_enabled(struct ata_device *dev)
 {
+#ifdef CONFIG_SATA_HOST
 	return (dev->flags & (ATA_DFLAG_PIO | ATA_DFLAG_NCQ_OFF |
 			      ATA_DFLAG_NCQ)) == ATA_DFLAG_NCQ;
+#else
+	return 0;
+#endif
 }
 
 static inline bool ata_fpdma_dsm_supported(struct ata_device *dev)
-- 
2.24.1