Merge branch 'master'
[linux-2.6.git] / drivers / scsi / libata-core.c
index 8be7dc0b47b849858c8d5b37872e7112fb8e3b31..2e022240051eb6ff069435457dd5750d0e2bd942 100644 (file)
@@ -2427,8 +2427,9 @@ static void ata_dev_init_params(struct ata_port *ap, struct ata_device *dev)
 static void ata_sg_clean(struct ata_queued_cmd *qc)
 {
        struct ata_port *ap = qc->ap;
-       struct scatterlist *sg = qc->sg;
+       struct scatterlist *sg = qc->__sg;
        int dir = qc->dma_dir;
+       void *pad_buf = NULL;
 
        assert(qc->flags & ATA_QCFLAG_DMAMAP);
        assert(sg != NULL);
@@ -2438,14 +2439,35 @@ static void ata_sg_clean(struct ata_queued_cmd *qc)
 
        DPRINTK("unmapping %u sg elements\n", qc->n_elem);
 
-       if (qc->flags & ATA_QCFLAG_SG)
+       /* if we padded the buffer out to 32-bit bound, and data
+        * xfer direction is from-device, we must copy from the
+        * pad buffer back into the supplied buffer
+        */
+       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) {
                dma_unmap_sg(ap->host_set->dev, sg, qc->n_elem, dir);
-       else
+               /* restore last sg */
+               sg[qc->orig_n_elem - 1].length += qc->pad_len;
+               if (pad_buf) {
+                       struct scatterlist *psg = &qc->pad_sgent;
+                       void *addr = kmap_atomic(psg->page, KM_IRQ0);
+                       memcpy(addr + psg->offset, pad_buf, qc->pad_len);
+                       kunmap_atomic(psg->page, KM_IRQ0);
+               }
+       } else {
                dma_unmap_single(ap->host_set->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);
+       }
 
        qc->flags &= ~ATA_QCFLAG_DMAMAP;
-       qc->sg = NULL;
+       qc->__sg = NULL;
 }
 
 /**
@@ -2461,15 +2483,15 @@ static void ata_sg_clean(struct ata_queued_cmd *qc)
  */
 static void ata_fill_sg(struct ata_queued_cmd *qc)
 {
-       struct scatterlist *sg = qc->sg;
        struct ata_port *ap = qc->ap;
-       unsigned int idx, nelem;
+       struct scatterlist *sg;
+       unsigned int idx;
 
-       assert(sg != NULL);
+       assert(qc->__sg != NULL);
        assert(qc->n_elem > 0);
 
        idx = 0;
-       for (nelem = qc->n_elem; nelem; nelem--,sg++) {
+       ata_for_each_sg(sg, qc) {
                u32 addr, offset;
                u32 sg_len, len;
 
@@ -2555,12 +2577,18 @@ void ata_qc_prep(struct ata_queued_cmd *qc)
 
 void ata_sg_init_one(struct ata_queued_cmd *qc, void *buf, unsigned int buflen)
 {
+       struct scatterlist *sg;
+
        qc->flags |= ATA_QCFLAG_SINGLE;
 
-       qc->sg = &qc->sgent;
+       memset(&qc->sgent, 0, sizeof(qc->sgent));
+       qc->__sg = &qc->sgent;
        qc->n_elem = 1;
+       qc->orig_n_elem = 1;
        qc->buf_virt = buf;
-       sg_init_one(qc->sg, buf, buflen);
+
+       sg = qc->__sg;
+       sg_init_one(sg, buf, buflen);
 }
 
 /**
@@ -2581,8 +2609,9 @@ void ata_sg_init(struct ata_queued_cmd *qc, struct scatterlist *sg,
                 unsigned int n_elem)
 {
        qc->flags |= ATA_QCFLAG_SG;
-       qc->sg = sg;
+       qc->__sg = sg;
        qc->n_elem = n_elem;
+       qc->orig_n_elem = n_elem;
 }
 
 /**
@@ -2602,9 +2631,32 @@ 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;
+       struct scatterlist *sg = qc->__sg;
        dma_addr_t dma_address;
 
+       /* 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;
+
+               assert(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;
+
+               DPRINTK("padding done, sg->length=%u pad_len=%u\n",
+                       sg->length, qc->pad_len);
+       }
+
        dma_address = dma_map_single(ap->host_set->dev, qc->buf_virt,
                                     sg->length, dir);
        if (dma_mapping_error(dma_address))
@@ -2636,12 +2688,47 @@ static int ata_sg_setup_one(struct ata_queued_cmd *qc)
 static int ata_sg_setup(struct ata_queued_cmd *qc)
 {
        struct ata_port *ap = qc->ap;
-       struct scatterlist *sg = qc->sg;
+       struct scatterlist *sg = qc->__sg;
+       struct scatterlist *lsg = &sg[qc->n_elem - 1];
        int n_elem, dir;
 
        VPRINTK("ENTER, ata%u\n", ap->id);
        assert(qc->flags & ATA_QCFLAG_SG);
 
+       /* we must lengthen transfers to end on a 32-bit boundary */
+       qc->pad_len = lsg->length & 3;
+       if (qc->pad_len) {
+               void *pad_buf = ap->pad + (qc->tag * ATA_DMA_PAD_SZ);
+               struct scatterlist *psg = &qc->pad_sgent;
+               unsigned int offset;
+
+               assert(qc->dev->class == ATA_DEV_ATAPI);
+
+               memset(pad_buf, 0, ATA_DMA_PAD_SZ);
+
+               /*
+                * psg->page/offset are used to copy to-be-written
+                * data in this function or read data in ata_sg_clean.
+                */
+               offset = lsg->offset + lsg->length - qc->pad_len;
+               psg->page = nth_page(lsg->page, offset >> PAGE_SHIFT);
+               psg->offset = offset_in_page(offset);
+
+               if (qc->tf.flags & ATA_TFLAG_WRITE) {
+                       void *addr = kmap_atomic(psg->page, KM_IRQ0);
+                       memcpy(pad_buf, addr + psg->offset, qc->pad_len);
+                       kunmap_atomic(psg->page, KM_IRQ0);
+               }
+
+               sg_dma_address(psg) = ap->pad_dma + (qc->tag * ATA_DMA_PAD_SZ);
+               sg_dma_len(psg) = ATA_DMA_PAD_SZ;
+               /* trim last sg */
+               lsg->length -= qc->pad_len;
+
+               DPRINTK("padding done, sg[%d].length=%u pad_len=%u\n",
+                       qc->n_elem - 1, lsg->length, qc->pad_len);
+       }
+
        dir = qc->dma_dir;
        n_elem = dma_map_sg(ap->host_set->dev, sg, qc->n_elem, dir);
        if (n_elem < 1)
@@ -2917,7 +3004,7 @@ static void ata_data_xfer(struct ata_port *ap, unsigned char *buf,
 static void ata_pio_sector(struct ata_queued_cmd *qc)
 {
        int do_write = (qc->tf.flags & ATA_TFLAG_WRITE);
-       struct scatterlist *sg = qc->sg;
+       struct scatterlist *sg = qc->__sg;
        struct ata_port *ap = qc->ap;
        struct page *page;
        unsigned int offset;
@@ -2967,7 +3054,7 @@ static void ata_pio_sector(struct ata_queued_cmd *qc)
 static void __atapi_pio_bytes(struct ata_queued_cmd *qc, unsigned int bytes)
 {
        int do_write = (qc->tf.flags & ATA_TFLAG_WRITE);
-       struct scatterlist *sg = qc->sg;
+       struct scatterlist *sg = qc->__sg;
        struct ata_port *ap = qc->ap;
        struct page *page;
        unsigned char *buf;
@@ -3000,7 +3087,7 @@ next_sg:
                return;
        }
 
-       sg = &qc->sg[qc->cursg];
+       sg = &qc->__sg[qc->cursg];
 
        page = sg->page;
        offset = sg->offset + qc->cursg_ofs;
@@ -3357,7 +3444,7 @@ struct ata_queued_cmd *ata_qc_new_init(struct ata_port *ap,
 
        qc = ata_qc_new(ap);
        if (qc) {
-               qc->sg = NULL;
+               qc->__sg = NULL;
                qc->flags = 0;
                qc->scsicmd = NULL;
                qc->ap = ap;
@@ -4046,6 +4133,12 @@ int ata_port_start (struct ata_port *ap)
        if (!ap->prd)
                return -ENOMEM;
 
+       ap->pad = dma_alloc_coherent(dev, ATA_DMA_PAD_BUF_SZ, &ap->pad_dma, GFP_KERNEL);
+       if (!ap->pad) {
+               dma_free_coherent(dev, ATA_PRD_TBL_SZ, ap->prd, ap->prd_dma);
+               return -ENOMEM;
+       }
+
        DPRINTK("prd alloc, virt %p, dma %llx\n", ap->prd, (unsigned long long) ap->prd_dma);
 
        return 0;
@@ -4069,6 +4162,7 @@ void ata_port_stop (struct ata_port *ap)
        struct device *dev = ap->host_set->dev;
 
        dma_free_coherent(dev, ATA_PRD_TBL_SZ, ap->prd, ap->prd_dma);
+       dma_free_coherent(dev, ATA_DMA_PAD_BUF_SZ, ap->pad, ap->pad_dma);
 }
 
 void ata_host_stop (struct ata_host_set *host_set)