ide: idedisk_supports_lba48() -> ata_id_lba48_enabled()

* Add ata_id_lba48_enabled() inline helper to <linux/ata.h>.

* idedisk_supports_lba48() -> ata_id_lba48_enabled()

  The latter one also checks validity of words 83 & 86.

Cc: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/include/linux/ata.h b/include/linux/ata.h
index d28aad991c75..8162257b474f 100644
--- a/include/linux/ata.h
+++ b/include/linux/ata.h
@@ -574,6 +574,15 @@ static inline int ata_id_has_lba48(const u16 *id)
         return id[ATA_ID_COMMAND_SET_2] & (1 << 10);
 }
 
+static inline int ata_id_lba48_enabled(const u16 *id)
+{
+        if (ata_id_has_lba48(id) == 0)
+                return 0;
+        if ((id[ATA_ID_CSF_DEFAULT] & 0xC000) != 0x4000)
+                return 0;
+        return id[ATA_ID_CFS_ENABLE_2] & (1 << 10);
+}
+
 static inline int ata_id_hpa_enabled(const u16 *id)
 {
         /* Yes children, word 83 valid bits cover word 82 data */