libata: Protect DMA core code by #ifdef CONFIG_HAS_DMA

If NO_DMA=y:

    ERROR: "bad_dma_ops" [drivers/ata/libata.ko] undefined!

To fix this, protect the DMA code by #ifdef CONFIG_HAS_DMA, and provide
dummies of ata_sg_clean() and ata_sg_setup() for the !CONFIG_HAS_DMA
case.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Tejun Heo <tj@kernel.org>

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index a7e3df5abaa3124f4ffcd4aff1fbd2d7e10635b8..dc70b5f997f1f13e32f15225cde4abfaf7a6308f 100644 (file)
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -4813,32 +4813,6 @@ static unsigned int ata_dev_init_params(struct ata_device *dev,
        return err_mask;
 }
 
-/**
- *     ata_sg_clean - Unmap DMA memory associated with command
- *     @qc: Command containing DMA memory to be released
- *
- *     Unmap all mapped DMA memory associated with this command.
- *
- *     LOCKING:
- *     spin_lock_irqsave(host lock)
- */
-static void ata_sg_clean(struct ata_queued_cmd *qc)
-{
-       struct ata_port *ap = qc->ap;
-       struct scatterlist *sg = qc->sg;
-       int dir = qc->dma_dir;
-
-       WARN_ON_ONCE(sg == NULL);
-
-       VPRINTK("unmapping %u sg elements\n", qc->n_elem);
-
-       if (qc->n_elem)
-               dma_unmap_sg(ap->dev, sg, qc->orig_n_elem, dir);
-
-       qc->flags &= ~ATA_QCFLAG_DMAMAP;
-       qc->sg = NULL;
-}
-
 /**
  *     atapi_check_dma - Check whether ATAPI DMA can be supported
  *     @qc: Metadata associated with taskfile to check
@@ -4923,6 +4897,34 @@ void ata_sg_init(struct ata_queued_cmd *qc, struct scatterlist *sg,
        qc->cursg = qc->sg;
 }
 
+#ifdef CONFIG_HAS_DMA
+
+/**
+ *     ata_sg_clean - Unmap DMA memory associated with command
+ *     @qc: Command containing DMA memory to be released
+ *
+ *     Unmap all mapped DMA memory associated with this command.
+ *
+ *     LOCKING:
+ *     spin_lock_irqsave(host lock)
+ */
+void ata_sg_clean(struct ata_queued_cmd *qc)
+{
+       struct ata_port *ap = qc->ap;
+       struct scatterlist *sg = qc->sg;
+       int dir = qc->dma_dir;
+
+       WARN_ON_ONCE(sg == NULL);
+
+       VPRINTK("unmapping %u sg elements\n", qc->n_elem);
+
+       if (qc->n_elem)
+               dma_unmap_sg(ap->dev, sg, qc->orig_n_elem, dir);
+
+       qc->flags &= ~ATA_QCFLAG_DMAMAP;
+       qc->sg = NULL;
+}
+
 /**
  *     ata_sg_setup - DMA-map the scatter-gather table associated with a command.
  *     @qc: Command with scatter-gather table to be mapped.
@@ -4955,6 +4957,13 @@ static int ata_sg_setup(struct ata_queued_cmd *qc)
        return 0;
 }
 
+#else /* !CONFIG_HAS_DMA */
+
+static inline void ata_sg_clean(struct ata_queued_cmd *qc) {}
+static inline int ata_sg_setup(struct ata_queued_cmd *qc) { return -1; }
+
+#endif /* !CONFIG_HAS_DMA */
+
 /**
  *     swap_buf_le16 - swap halves of 16-bit words in place
  *     @buf:  Buffer to swap