| Message ID | 20160615111308.28739-5-niklas.soderlund+renesas@ragnatech.se (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Geert Uytterhoeven |
| Headers | show |
Hi Niklas, Thank you for the patch. On Wednesday 15 Jun 2016 13:13:08 Niklas Söderlund wrote: > From: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> > > Cookies corresponding to pending transfers have a residue value equal to > the full size of the corresponding descriptor. The driver miscomputes > that and uses the size of the active descriptor instead. Fix it. > > Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> > Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> > [geert: Also check desc.active list] > Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> > Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> > --- > drivers/dma/sh/rcar-dmac.c | 32 ++++++++++++++++++++++++++++++-- > 1 file changed, 30 insertions(+), 2 deletions(-) > > diff --git a/drivers/dma/sh/rcar-dmac.c b/drivers/dma/sh/rcar-dmac.c > index 59951fb..86aef28 100644 > --- a/drivers/dma/sh/rcar-dmac.c > +++ b/drivers/dma/sh/rcar-dmac.c > @@ -1145,19 +1145,47 @@ static unsigned int > rcar_dmac_chan_get_residue(struct rcar_dmac_chan *chan, struct > rcar_dmac_desc *desc = chan->desc.running; > struct rcar_dmac_xfer_chunk *running = NULL; > struct rcar_dmac_xfer_chunk *chunk; > + enum dma_status status; > unsigned int residue = 0; > unsigned int dptr = 0; > > if (!desc) > return 0; > > + One blank line is enough. Apart from that your change to my patch looks good, thank you for fixing it. > + /* > + * If the cookie corresponds to a descriptor that has been completed > + * there is no residue. The same check has already been performed by the > + * caller but without holding the channel lock, so the descriptor could > + * now be complete. > + */ > + status = dma_cookie_status(&chan->chan, cookie, NULL); > + if (status == DMA_COMPLETE) > + return 0; > + > /* > * If the cookie doesn't correspond to the currently running transfer > * then the descriptor hasn't been processed yet, and the residue is > * equal to the full descriptor size. > */ > - if (cookie != desc->async_tx.cookie) > - return desc->size; > + if (cookie != desc->async_tx.cookie) { > + list_for_each_entry(desc, &chan->desc.pending, node) { > + if (cookie == desc->async_tx.cookie) > + return desc->size; > + } > + list_for_each_entry(desc, &chan->desc.active, node) { > + if (cookie == desc->async_tx.cookie) > + return desc->size; > + } > + > + /* > + * No descriptor found for the cookie, there's thus no residue. > + * This shouldn't happen if the calling driver passes a correct > + * cookie value. > + */ > + WARN(1, "No descriptor for cookie!"); > + return 0; > + } > > /* > * In descriptor mode the descriptor running pointer is not maintained
diff --git a/drivers/dma/sh/rcar-dmac.c b/drivers/dma/sh/rcar-dmac.c index 59951fb..86aef28 100644 --- a/drivers/dma/sh/rcar-dmac.c +++ b/drivers/dma/sh/rcar-dmac.c @@ -1145,19 +1145,47 @@ static unsigned int rcar_dmac_chan_get_residue(struct rcar_dmac_chan *chan, struct rcar_dmac_desc *desc = chan->desc.running; struct rcar_dmac_xfer_chunk *running = NULL; struct rcar_dmac_xfer_chunk *chunk; + enum dma_status status; unsigned int residue = 0; unsigned int dptr = 0; if (!desc) return 0; + + /* + * If the cookie corresponds to a descriptor that has been completed + * there is no residue. The same check has already been performed by the + * caller but without holding the channel lock, so the descriptor could + * now be complete. + */ + status = dma_cookie_status(&chan->chan, cookie, NULL); + if (status == DMA_COMPLETE) + return 0; + /* * If the cookie doesn't correspond to the currently running transfer * then the descriptor hasn't been processed yet, and the residue is * equal to the full descriptor size. */ - if (cookie != desc->async_tx.cookie) - return desc->size; + if (cookie != desc->async_tx.cookie) { + list_for_each_entry(desc, &chan->desc.pending, node) { + if (cookie == desc->async_tx.cookie) + return desc->size; + } + list_for_each_entry(desc, &chan->desc.active, node) { + if (cookie == desc->async_tx.cookie) + return desc->size; + } + + /* + * No descriptor found for the cookie, there's thus no residue. + * This shouldn't happen if the calling driver passes a correct + * cookie value. + */ + WARN(1, "No descriptor for cookie!"); + return 0; + } /* * In descriptor mode the descriptor running pointer is not maintained