libata-link: introduce ata_link

Introduce ata_link.  It abstracts PHY and sits between ata_port and
ata_device.  This new level of abstraction is necessary to support
SATA Port Multiplier, which basically adds a bunch of links (PHYs) to
a ATA host port.  Fields related to command execution, spd_limit and
EH are per-link and thus moved to ata_link.

This patch only defines the host link.  Multiple link handling will be
added later.  Also, a lot of ap->link derefences are added but many of
them will be removed as each part is converted to deal directly with
ata_link instead of ata_port.

This patch introduces no behavior change.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: James Bottomley <James.Bottomley@SteelEye.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/drivers/ata/libata-sff.c b/drivers/ata/libata-sff.c
index 8023167bbbe..2100cd61ed6 100644
--- a/drivers/ata/libata-sff.c
+++ b/drivers/ata/libata-sff.c
@@ -445,7 +445,7 @@ void ata_bmdma_drive_eh(struct ata_port *ap, ata_prereset_fn_t prereset,
         unsigned long flags;
         int thaw = 0;
 
-        qc = __ata_qc_from_tag(ap, ap->active_tag);
+        qc = __ata_qc_from_tag(ap, ap->link.active_tag);
         if (qc && !(qc->flags & ATA_QCFLAG_FAILED))
                 qc = NULL;
 
@@ -909,7 +909,7 @@ unsigned long ata_pci_default_filter(struct ata_device *adev, unsigned long xfer
         /* Filter out DMA modes if the device has been configured by
            the BIOS as PIO only */
 
-        if (adev->ap->ioaddr.bmdma_addr == 0)
+        if (adev->link->ap->ioaddr.bmdma_addr == 0)
                 xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
         return xfer_mask;
 }