libata: HPA support

Signed-off-by: Alan Cox <alan@redhat.com>

Add support for ignoring the BIOS HPA result (off by default) and setting
the disk to the full available size unless already frozen.

Tested with various platforms/disks and confirmed to work with the
Macintosh (which broke earlier) and ata_piix (breakage due to the LBA48
readback that Tejun fixed).

For normal users this brings us, I believe, to feature parity with old IDE
(and of course more featured in some areas too).
Signed-off-by: Jeff Garzik <jeff@garzik.org>

2 files changed, 3 insertions, 0 deletions

diff --git a/include/linux/ata.h b/include/linux/ata.h
index ffb6cdc5010d..f4dc8dfeadc2 100644
--- a/include/linux/ata.h
+++ b/include/linux/ata.h
@@ -159,6 +159,8 @@ enum {
         ATA_CMD_INIT_DEV_PARAMS = 0x91,
         ATA_CMD_READ_NATIVE_MAX = 0xF8,
         ATA_CMD_READ_NATIVE_MAX_EXT = 0x27,
+        ATA_CMD_SET_MAX         = 0xF9,
+        ATA_CMD_SET_MAX_EXT     = 0x37,
         ATA_CMD_READ_LOG_EXT    = 0x2f,
 
         /* READ_LOG_EXT pages */
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 7c14a52079d5..73b86dd30aec 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -446,6 +446,7 @@ struct ata_device {
         struct scsi_device      *sdev;          /* attached SCSI device */
         /* n_sector is used as CLEAR_OFFSET, read comment above CLEAR_OFFSET */
         u64                     n_sectors;      /* size of device, if ATA */
+        u64                     n_sectors_boot; /* size of ATA device at startup */
         unsigned int            class;          /* ATA_DEV_xxx */
         u16                     id[ATA_ID_WORDS]; /* IDENTIFY xxx DEVICE data */
         u8                      pio_mode;