diff options
Diffstat (limited to 'include/linux/libata.h')
| -rw-r--r-- | include/linux/libata.h | 52 |
1 files changed, 51 insertions, 1 deletions
diff --git a/include/linux/libata.h b/include/linux/libata.h index 0ba3af7a123..dcd17e7458a 100644 --- 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), @@ -249,9 +253,12 @@ 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; @@ -262,9 +269,11 @@ 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; @@ -310,6 +319,9 @@ 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 */ @@ -512,6 +524,31 @@ extern int pci_test_config_bits(struct pci_dev *pdev, const struct pci_bits *bit #endif /* CONFIG_PCI */ +static inline int +ata_sg_is_last(struct scatterlist *sg, struct ata_queued_cmd *qc) +{ + if (sg == &qc->pad_sgent) + return 1; + if (qc->pad_len) + return 0; + if (((sg - qc->__sg) + 1) == qc->n_elem) + return 1; + return 0; +} + +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; @@ -740,4 +777,17 @@ static inline unsigned int __ac_err_mask(u8 status) return mask; } +static inline int ata_pad_alloc(struct ata_port *ap, struct device *dev) +{ + ap->pad_dma = 0; + ap->pad = dma_alloc_coherent(dev, ATA_DMA_PAD_BUF_SZ, + &ap->pad_dma, GFP_KERNEL); + return (ap->pad == NULL) ? -ENOMEM : 0; +} + +static inline void ata_pad_free(struct ata_port *ap, struct device *dev) +{ + dma_free_coherent(dev, ATA_DMA_PAD_BUF_SZ, ap->pad, ap->pad_dma); +} + #endif /* __LINUX_LIBATA_H__ */ |