On Fri, Oct 18, 2013 at 07:35:31PM +0200, Bartlomiej Zolnierkiewicz wrote: > Use the generic unmap object to unmap dma buffers. > > As NTB can be compiled without DMA_ENGINE support add
Seems like the stubs should be added outside of this patch. Also, the comment implies that NTB could not be compiled without DMA_ENGINE support before, which it could be. > stub functions to <linux/dmaengine.h> for dma_set_unmap(), > dmaengine_get_unmap_data() and dmaengine_unmap_put(). > > Cc: Dan Williams <[email protected]> > Cc: Vinod Koul <[email protected]> > Cc: Tomasz Figa <[email protected]> > Cc: Dave Jiang <[email protected]> > Cc: Jon Mason <[email protected]> > Signed-off-by: Bartlomiej Zolnierkiewicz <[email protected]> > Signed-off-by: Kyungmin Park <[email protected]> > --- > drivers/ntb/ntb_transport.c | 63 > +++++++++++++++++++++++++++++++++------------ > include/linux/dmaengine.h | 15 +++++++++++ > 2 files changed, 61 insertions(+), 17 deletions(-) > > diff --git a/drivers/ntb/ntb_transport.c b/drivers/ntb/ntb_transport.c > index 12a9e83..fc6bbf1 100644 > --- a/drivers/ntb/ntb_transport.c > +++ b/drivers/ntb/ntb_transport.c > @@ -1034,7 +1034,7 @@ static void ntb_async_rx(struct ntb_queue_entry *entry, > void *offset, > struct dma_chan *chan = qp->dma_chan; > struct dma_device *device; > size_t pay_off, buff_off; > - dma_addr_t src, dest; > + struct dmaengine_unmap_data *unmap; > dma_cookie_t cookie; > void *buf = entry->buf; > unsigned long flags; > @@ -1054,27 +1054,41 @@ static void ntb_async_rx(struct ntb_queue_entry > *entry, void *offset, > if (!is_dma_copy_aligned(device, pay_off, buff_off, len)) > goto err1; > > - dest = dma_map_single(device->dev, buf, len, DMA_FROM_DEVICE); > - if (dma_mapping_error(device->dev, dest)) > + unmap = dmaengine_get_unmap_data(device->dev, 2, GFP_NOIO); > + if (!unmap) > goto err1; > > - src = dma_map_single(device->dev, offset, len, DMA_TO_DEVICE); > - if (dma_mapping_error(device->dev, src)) > + unmap->addr[0] = dma_map_page(device->dev, virt_to_page(offset), > + pay_off, len, DMA_TO_DEVICE); > + if (dma_mapping_error(device->dev, unmap->addr[0])) > goto err2; > > - flags = DMA_COMPL_DEST_UNMAP_SINGLE | DMA_COMPL_SRC_UNMAP_SINGLE | > + unmap->to_cnt = 1; > + > + unmap->addr[1] = dma_map_page(device->dev, virt_to_page(buf), > + buff_off, len, DMA_FROM_DEVICE); > + if (dma_mapping_error(device->dev, unmap->addr[1])) > + goto err2; > + > + unmap->from_cnt = 1; > + > + flags = DMA_COMPL_SKIP_SRC_UNMAP | DMA_COMPL_SKIP_DEST_UNMAP | > DMA_PREP_INTERRUPT; > - txd = device->device_prep_dma_memcpy(chan, dest, src, len, flags); > + txd = device->device_prep_dma_memcpy(chan, unmap->addr[1], > + unmap->addr[0], len, flags); I must say, as a user I dislike this interface much less than the previous. Can we abstract all of this away in a helper function that simply takes the src, dest, and len, then maps and calls device_prep_dma_memcpy? The driver does not keep track of the dmaengine_unmap_data, so the helper function could simply return an error if something isn't happy. Thoughts? Thanks, Jon > if (!txd) > - goto err3; > + goto err2; > > txd->callback = ntb_rx_copy_callback; > txd->callback_param = entry; > + dma_set_unmap(txd, unmap); > > cookie = dmaengine_submit(txd); > if (dma_submit_error(cookie)) > goto err3; > > + dmaengine_unmap_put(unmap); > + > qp->last_cookie = cookie; > > qp->rx_async++; > @@ -1082,9 +1096,9 @@ static void ntb_async_rx(struct ntb_queue_entry *entry, > void *offset, > return; > > err3: > - dma_unmap_single(device->dev, src, len, DMA_TO_DEVICE); > + dmaengine_unmap_put(unmap); > err2: > - dma_unmap_single(device->dev, dest, len, DMA_FROM_DEVICE); > + dmaengine_unmap_put(unmap); > err1: > /* If the callbacks come out of order, the writing of the index to the > * last completed will be out of order. This may result in the > @@ -1245,7 +1259,8 @@ static void ntb_async_tx(struct ntb_transport_qp *qp, > struct dma_chan *chan = qp->dma_chan; > struct dma_device *device; > size_t dest_off, buff_off; > - dma_addr_t src, dest; > + struct dmaengine_unmap_data *unmap; > + dma_addr_t dest; > dma_cookie_t cookie; > void __iomem *offset; > size_t len = entry->len; > @@ -1273,28 +1288,42 @@ static void ntb_async_tx(struct ntb_transport_qp *qp, > if (!is_dma_copy_aligned(device, buff_off, dest_off, len)) > goto err; > > - src = dma_map_single(device->dev, buf, len, DMA_TO_DEVICE); > - if (dma_mapping_error(device->dev, src)) > + unmap = dmaengine_get_unmap_data(device->dev, 1, GFP_NOIO); > + if (!unmap) > goto err; > > - flags = DMA_COMPL_SRC_UNMAP_SINGLE | DMA_PREP_INTERRUPT; > - txd = device->device_prep_dma_memcpy(chan, dest, src, len, flags); > + unmap->addr[0] = dma_map_page(device->dev, virt_to_page(buf), > + buff_off, len, DMA_TO_DEVICE); > + if (dma_mapping_error(device->dev, unmap->addr[0])) > + goto err1; > + > + unmap->to_cnt = 1; > + > + flags = DMA_COMPL_SKIP_SRC_UNMAP | DMA_COMPL_SKIP_DEST_UNMAP | > + DMA_PREP_INTERRUPT; > + txd = device->device_prep_dma_memcpy(chan, dest, unmap->addr[0], len, > + flags); > if (!txd) > goto err1; > > txd->callback = ntb_tx_copy_callback; > txd->callback_param = entry; > + dma_set_unmap(txd, unmap); > > cookie = dmaengine_submit(txd); > if (dma_submit_error(cookie)) > - goto err1; > + goto err2; > + > + dmaengine_unmap_put(unmap); > > dma_async_issue_pending(chan); > qp->tx_async++; > > return; > +err2: > + dmaengine_unmap_put(unmap); > err1: > - dma_unmap_single(device->dev, src, len, DMA_TO_DEVICE); > + dmaengine_unmap_put(unmap); > err: > ntb_memcpy_tx(entry, offset); > qp->tx_memcpy++; > diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h > index dc98bc5..3782cdb 100644 > --- a/include/linux/dmaengine.h > +++ b/include/linux/dmaengine.h > @@ -457,6 +457,7 @@ struct dma_async_tx_descriptor { > #endif > }; > > +#ifdef CONFIG_DMA_ENGINE > static inline void dma_set_unmap(struct dma_async_tx_descriptor *tx, > struct dmaengine_unmap_data *unmap) > { > @@ -467,6 +468,20 @@ static inline void dma_set_unmap(struct > dma_async_tx_descriptor *tx, > struct dmaengine_unmap_data * > dmaengine_get_unmap_data(struct device *dev, int nr, gfp_t flags); > void dmaengine_unmap_put(struct dmaengine_unmap_data *unmap); > +#else > +static inline void dma_set_unmap(struct dma_async_tx_descriptor *tx, > + struct dmaengine_unmap_data *unmap) > +{ > +} > +static inline struct dmaengine_unmap_data * > +dmaengine_get_unmap_data(struct device *dev, int nr, gfp_t flags) > +{ > + return NULL; > +} > +static inline void dmaengine_unmap_put(struct dmaengine_unmap_data *unmap) > +{ > +} > +#endif > > static inline void dma_descriptor_unmap(struct dma_async_tx_descriptor *tx) > { > -- > 1.8.2.3 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
