Merge branch 'upstream'

[linux-2.6-block.git] / include / linux / libata.h

diff --git a/include/linux/libata.h b/include/linux/libata.h
index 0261c55f34837a4049e9651770cbabb7304efa9b..d3f58a796c3a371f1497af11c581e541e7862908 100644 (file)
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -155,6 +155,10 @@ enum {
        ATA_SHIFT_UDMA          = 0,
        ATA_SHIFT_MWDMA         = 8,
        ATA_SHIFT_PIO           = 11,
+
+       /* size of buffer to pad xfers ending on unaligned boundaries */
+       ATA_DMA_PAD_SZ          = 4,
+       ATA_DMA_PAD_BUF_SZ      = ATA_DMA_PAD_SZ * ATA_MAX_QUEUE,
        
        /* Masks for port functions */
        ATA_PORT_PRIMARY        = (1 << 0),
@@ -242,9 +246,12 @@ struct ata_queued_cmd {
        unsigned long           flags;          /* ATA_QCFLAG_xxx */
        unsigned int            tag;
        unsigned int            n_elem;
+       unsigned int            orig_n_elem;
 
        int                     dma_dir;
 
+       unsigned int            pad_len;
+
        unsigned int            nsect;
        unsigned int            cursect;
 
@@ -255,9 +262,11 @@ struct ata_queued_cmd {
        unsigned int            cursg_ofs;
 
        struct scatterlist      sgent;
+       struct scatterlist      pad_sgent;
        void                    *buf_virt;
 
-       struct scatterlist      *sg;
+       /* DO NOT iterate over __sg manually, use ata_for_each_sg() */
+       struct scatterlist      *__sg;
 
        ata_qc_cb_t             complete_fn;
 
@@ -303,6 +312,9 @@ struct ata_port {
        struct ata_prd          *prd;    /* our SG list */
        dma_addr_t              prd_dma; /* and its DMA mapping */
 
+       void                    *pad;   /* array of DMA pad buffers */
+       dma_addr_t              pad_dma;
+
        struct ata_ioports      ioaddr; /* ATA cmd/ctl/dma register blocks */
 
        u8                      ctl;    /* cache of ATA control register */
@@ -468,6 +480,19 @@ extern int pci_test_config_bits(struct pci_dev *pdev, struct pci_bits *bits);
 #endif /* CONFIG_PCI */
 
 
+static inline struct scatterlist *
+ata_qc_next_sg(struct scatterlist *sg, struct ata_queued_cmd *qc)
+{
+       if (sg == &qc->pad_sgent)
+               return NULL;
+       if (++sg - qc->__sg < qc->n_elem)
+               return sg;
+       return qc->pad_len ? &qc->pad_sgent : NULL;
+}
+
+#define ata_for_each_sg(sg, qc) \
+       for (sg = qc->__sg; sg; sg = ata_qc_next_sg(sg, qc))
+
 static inline unsigned int ata_tag_valid(unsigned int tag)
 {
        return (tag < ATA_MAX_QUEUE) ? 1 : 0;