libata: kill non-sg DMA interface

With atapi_request_sense() converted to use sg, there's no user of
non-sg interface.  Kill non-sg interface.

* ATA_QCFLAG_SINGLE and ATA_QCFLAG_SG are removed.  ATA_QCFLAG_DMAMAP
  is used instead.  (this way no LLD change is necessary)

* qc->buf_virt is removed.

* ata_sg_init_one() and ata_sg_setup_one() are removed.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Rusty Russel <rusty@rustcorp.com.au>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 39cedd949ed4cea967742661db5b663727724890..76360f0ca20d267cd88556e535ad03f616da71bc 100644 (file)
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -4478,9 +4478,6 @@ void ata_sg_clean(struct ata_queued_cmd *qc)
        WARN_ON(!(qc->flags & ATA_QCFLAG_DMAMAP));
        WARN_ON(sg == NULL);
 
-       if (qc->flags & ATA_QCFLAG_SINGLE)
-               WARN_ON(qc->n_elem > 1);
-
        VPRINTK("unmapping %u sg elements\n", qc->n_elem);
 
        /* if we padded the buffer out to 32-bit bound, and data
@@ -4490,27 +4487,15 @@ void ata_sg_clean(struct ata_queued_cmd *qc)
        if (qc->pad_len && !(qc->tf.flags & ATA_TFLAG_WRITE))
                pad_buf = ap->pad + (qc->tag * ATA_DMA_PAD_SZ);
 
-       if (qc->flags & ATA_QCFLAG_SG) {
-               if (qc->n_elem)
-                       dma_unmap_sg(ap->dev, sg, qc->n_elem, dir);
-               /* restore last sg */
-               sg_last(sg, qc->orig_n_elem)->length += qc->pad_len;
-               if (pad_buf) {
-                       struct scatterlist *psg = &qc->pad_sgent;
-                       void *addr = kmap_atomic(sg_page(psg), KM_IRQ0);
-                       memcpy(addr + psg->offset, pad_buf, qc->pad_len);
-                       kunmap_atomic(addr, KM_IRQ0);
-               }
-       } else {
-               if (qc->n_elem)
-                       dma_unmap_single(ap->dev,
-                               sg_dma_address(&sg[0]), sg_dma_len(&sg[0]),
-                               dir);
-               /* restore sg */
-               sg->length += qc->pad_len;
-               if (pad_buf)
-                       memcpy(qc->buf_virt + sg->length - qc->pad_len,
-                              pad_buf, qc->pad_len);
+       if (qc->n_elem)
+               dma_unmap_sg(ap->dev, sg, qc->n_elem, dir);
+       /* restore last sg */
+       sg_last(sg, qc->orig_n_elem)->length += qc->pad_len;
+       if (pad_buf) {
+               struct scatterlist *psg = &qc->pad_sgent;
+               void *addr = kmap_atomic(sg_page(psg), KM_IRQ0);
+               memcpy(addr + psg->offset, pad_buf, qc->pad_len);
+               kunmap_atomic(addr, KM_IRQ0);
        }
 
        qc->flags &= ~ATA_QCFLAG_DMAMAP;
@@ -4764,33 +4749,6 @@ void ata_dumb_qc_prep(struct ata_queued_cmd *qc)
 
 void ata_noop_qc_prep(struct ata_queued_cmd *qc) { }
 
-/**
- *     ata_sg_init_one - Associate command with memory buffer
- *     @qc: Command to be associated
- *     @buf: Memory buffer
- *     @buflen: Length of memory buffer, in bytes.
- *
- *     Initialize the data-related elements of queued_cmd @qc
- *     to point to a single memory buffer, @buf of byte length @buflen.
- *
- *     LOCKING:
- *     spin_lock_irqsave(host lock)
- */
-
-void ata_sg_init_one(struct ata_queued_cmd *qc, void *buf, unsigned int buflen)
-{
-       qc->flags |= ATA_QCFLAG_SINGLE;
-
-       qc->__sg = &qc->sgent;
-       qc->n_elem = 1;
-       qc->orig_n_elem = 1;
-       qc->buf_virt = buf;
-       qc->nbytes = buflen;
-       qc->cursg = qc->__sg;
-
-       sg_init_one(&qc->sgent, buf, buflen);
-}
-
 /**
  *     ata_sg_init - Associate command with scatter-gather table.
  *     @qc: Command to be associated
@@ -4808,82 +4766,13 @@ void ata_sg_init_one(struct ata_queued_cmd *qc, void *buf, unsigned int buflen)
 void ata_sg_init(struct ata_queued_cmd *qc, struct scatterlist *sg,
                 unsigned int n_elem)
 {
-       qc->flags |= ATA_QCFLAG_SG;
+       qc->flags |= ATA_QCFLAG_DMAMAP;
        qc->__sg = sg;
        qc->n_elem = n_elem;
        qc->orig_n_elem = n_elem;
        qc->cursg = qc->__sg;
 }
 
-/**
- *     ata_sg_setup_one - DMA-map the memory buffer associated with a command.
- *     @qc: Command with memory buffer to be mapped.
- *
- *     DMA-map the memory buffer associated with queued_cmd @qc.
- *
- *     LOCKING:
- *     spin_lock_irqsave(host lock)
- *
- *     RETURNS:
- *     Zero on success, negative on error.
- */
-
-static int ata_sg_setup_one(struct ata_queued_cmd *qc)
-{
-       struct ata_port *ap = qc->ap;
-       int dir = qc->dma_dir;
-       struct scatterlist *sg = qc->__sg;
-       dma_addr_t dma_address;
-       int trim_sg = 0;
-
-       /* we must lengthen transfers to end on a 32-bit boundary */
-       qc->pad_len = sg->length & 3;
-       if (qc->pad_len) {
-               void *pad_buf = ap->pad + (qc->tag * ATA_DMA_PAD_SZ);
-               struct scatterlist *psg = &qc->pad_sgent;
-
-               WARN_ON(qc->dev->class != ATA_DEV_ATAPI);
-
-               memset(pad_buf, 0, ATA_DMA_PAD_SZ);
-
-               if (qc->tf.flags & ATA_TFLAG_WRITE)
-                       memcpy(pad_buf, qc->buf_virt + sg->length - qc->pad_len,
-                              qc->pad_len);
-
-               sg_dma_address(psg) = ap->pad_dma + (qc->tag * ATA_DMA_PAD_SZ);
-               sg_dma_len(psg) = ATA_DMA_PAD_SZ;
-               /* trim sg */
-               sg->length -= qc->pad_len;
-               if (sg->length == 0)
-                       trim_sg = 1;
-
-               DPRINTK("padding done, sg->length=%u pad_len=%u\n",
-                       sg->length, qc->pad_len);
-       }
-
-       if (trim_sg) {
-               qc->n_elem--;
-               goto skip_map;
-       }
-
-       dma_address = dma_map_single(ap->dev, qc->buf_virt,
-                                    sg->length, dir);
-       if (dma_mapping_error(dma_address)) {
-               /* restore sg */
-               sg->length += qc->pad_len;
-               return -1;
-       }
-
-       sg_dma_address(sg) = dma_address;
-       sg_dma_len(sg) = sg->length;
-
-skip_map:
-       DPRINTK("mapped buffer of %d bytes for %s\n", sg_dma_len(sg),
-               qc->tf.flags & ATA_TFLAG_WRITE ? "write" : "read");
-
-       return 0;
-}
-
 /**
  *     ata_sg_setup - DMA-map the scatter-gather table associated with a command.
  *     @qc: Command with scatter-gather table to be mapped.
@@ -4906,7 +4795,7 @@ static int ata_sg_setup(struct ata_queued_cmd *qc)
        int n_elem, pre_n_elem, dir, trim_sg = 0;
 
        VPRINTK("ENTER, ata%u\n", ap->print_id);
-       WARN_ON(!(qc->flags & ATA_QCFLAG_SG));
+       WARN_ON(!(qc->flags & ATA_QCFLAG_DMAMAP));
 
        /* we must lengthen transfers to end on a 32-bit boundary */
        qc->pad_len = lsg->length & 3;
@@ -6025,16 +5914,10 @@ void ata_qc_issue(struct ata_queued_cmd *qc)
 
        if (ata_is_dma(prot) || (ata_is_pio(prot) &&
                                 (ap->flags & ATA_FLAG_PIO_DMA))) {
-               if (qc->flags & ATA_QCFLAG_SG) {
-                       if (ata_sg_setup(qc))
-                               goto sg_err;
-               } else if (qc->flags & ATA_QCFLAG_SINGLE) {
-                       if (ata_sg_setup_one(qc))
-                               goto sg_err;
-               }
-       } else {
-               qc->flags &= ~ATA_QCFLAG_DMAMAP;
-       }
+               if (ata_sg_setup(qc))
+                       goto sg_err;
+       } else
+               qc->flags &= ATA_QCFLAG_DMAMAP;
 
        /* if device is sleeping, schedule softreset and abort the link */
        if (unlikely(qc->dev->flags & ATA_DFLAG_SLEEPING)) {
@@ -7612,7 +7495,6 @@ EXPORT_SYMBOL_GPL(ata_host_register);
 EXPORT_SYMBOL_GPL(ata_host_activate);
 EXPORT_SYMBOL_GPL(ata_host_detach);
 EXPORT_SYMBOL_GPL(ata_sg_init);
-EXPORT_SYMBOL_GPL(ata_sg_init_one);
 EXPORT_SYMBOL_GPL(ata_hsm_move);
 EXPORT_SYMBOL_GPL(ata_qc_complete);
 EXPORT_SYMBOL_GPL(ata_qc_complete_multiple);

diff --git a/include/linux/libata.h b/include/linux/libata.h
index 7fa96cb4f6db0f7efa35af29f9e00307cb7dbaae..acd90ad78417863c578c3497680eae701b6416e0 100644 (file)
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -219,9 +219,7 @@ enum {
 
        /* struct ata_queued_cmd flags */
        ATA_QCFLAG_ACTIVE       = (1 << 0), /* cmd not yet ack'd to scsi lyer */
-       ATA_QCFLAG_SG           = (1 << 1), /* have s/g table? */
-       ATA_QCFLAG_SINGLE       = (1 << 2), /* no s/g, just a single buffer */
-       ATA_QCFLAG_DMAMAP       = ATA_QCFLAG_SG | ATA_QCFLAG_SINGLE,
+       ATA_QCFLAG_DMAMAP       = (1 << 1), /* SG table is DMA mapped */
        ATA_QCFLAG_IO           = (1 << 3), /* standard IO command */
        ATA_QCFLAG_RESULT_TF    = (1 << 4), /* result TF requested */
        ATA_QCFLAG_CLEAR_EXCL   = (1 << 5), /* clear excl_link on completion */
@@ -475,7 +473,6 @@ struct ata_queued_cmd {
 
        struct scatterlist      sgent;
        struct scatterlist      pad_sgent;
-       void                    *buf_virt;
 
        /* DO NOT iterate over __sg manually, use ata_for_each_sg() */
        struct scatterlist      *__sg;
@@ -891,8 +888,6 @@ extern void ata_dumb_qc_prep(struct ata_queued_cmd *qc);
 extern void ata_qc_prep(struct ata_queued_cmd *qc);
 extern void ata_noop_qc_prep(struct ata_queued_cmd *qc);
 extern unsigned int ata_qc_issue_prot(struct ata_queued_cmd *qc);
-extern void ata_sg_init_one(struct ata_queued_cmd *qc, void *buf,
-               unsigned int buflen);
 extern void ata_sg_init(struct ata_queued_cmd *qc, struct scatterlist *sg,
                 unsigned int n_elem);
 extern unsigned int ata_dev_classify(const struct ata_taskfile *tf);