| Message ID | m338i9iwa6.fsf@intrepid.localdomain |
|---|---|
| State | New |
| Headers | show |
On Sun, 23 Mar 2014 01:38:41 +0100 Krzysztof Halasa <khc@pm.waw.pl> wrote: > This is equivalent of a more generic change to lib/dma-debug.c which is > present since v2.6.33: > > commit 42d53b4ff7d61487d18274ebdf1f70c1aef6f122 > dma-debug: allow DMA_BIDIRECTIONAL mappings to be synced with DMA_FROM_DEVICE > and DMA_TO_DEVICE. > > There is no need to perform full BIDIR sync (copying the buffers in case > of swiotlb and similar schemes) if we know that the owner (CPU or device) > hasn't altered the data. > > Addresses the false-positive reported at > http://bugzilla.kernel.org/show_bug.cgi?id=14169 > > Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl> Tested-by: Simon Kagstrom <simon.kagstrom@netinsight.net> (Tested with a e100 device which previously triggered this). // Simon
On Sunday 23 March 2014, Krzysztof Halasa wrote: > This is equivalent of a more generic change to lib/dma-debug.c which is > present since v2.6.33: > > commit 42d53b4ff7d61487d18274ebdf1f70c1aef6f122 > dma-debug: allow DMA_BIDIRECTIONAL mappings to be synced with DMA_FROM_DEVICE > and DMA_TO_DEVICE. > > There is no need to perform full BIDIR sync (copying the buffers in case > of swiotlb and similar schemes) if we know that the owner (CPU or device) > hasn't altered the data. > > Addresses the false-positive reported at > http://bugzilla.kernel.org/show_bug.cgi?id=14169 > > Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl> Looks good to me. Can you add it to Russell's patch tracker? Acked-by: Arnd Bergmann <arnd@arndb.de> Arnd > diff --git a/arch/arm/common/dmabounce.c b/arch/arm/common/dmabounce.c > index 1143c4d..b4c17cf 100644 > --- a/arch/arm/common/dmabounce.c > +++ b/arch/arm/common/dmabounce.c > @@ -375,7 +375,7 @@ static int __dmabounce_sync_for_cpu(struct device *dev, dma_addr_t addr, > > off = addr - buf->safe_dma_addr; > > - BUG_ON(buf->direction != dir); > + BUG_ON(buf->direction != dir && buf->direction != DMA_BIDIRECTIONAL); > > dev_dbg(dev, "%s: unsafe buffer %p (dma=%#x off=%#lx) mapped to %p (dma=%#x)\n", > __func__, buf->ptr, virt_to_dma(dev, buf->ptr), off, > @@ -415,7 +415,7 @@ static int __dmabounce_sync_for_device(struct device *dev, dma_addr_t addr, > > off = addr - buf->safe_dma_addr; > > - BUG_ON(buf->direction != dir); > + BUG_ON(buf->direction != dir && buf->direction != DMA_BIDIRECTIONAL); > > dev_dbg(dev, "%s: unsafe buffer %p (dma=%#x off=%#lx) mapped to %p (dma=%#x)\n", > __func__, buf->ptr, virt_to_dma(dev, buf->ptr), off, >
diff --git a/arch/arm/common/dmabounce.c b/arch/arm/common/dmabounce.c index 1143c4d..b4c17cf 100644 --- a/arch/arm/common/dmabounce.c +++ b/arch/arm/common/dmabounce.c @@ -375,7 +375,7 @@ static int __dmabounce_sync_for_cpu(struct device *dev, dma_addr_t addr, off = addr - buf->safe_dma_addr; - BUG_ON(buf->direction != dir); + BUG_ON(buf->direction != dir && buf->direction != DMA_BIDIRECTIONAL); dev_dbg(dev, "%s: unsafe buffer %p (dma=%#x off=%#lx) mapped to %p (dma=%#x)\n", __func__, buf->ptr, virt_to_dma(dev, buf->ptr), off, @@ -415,7 +415,7 @@ static int __dmabounce_sync_for_device(struct device *dev, dma_addr_t addr, off = addr - buf->safe_dma_addr; - BUG_ON(buf->direction != dir); + BUG_ON(buf->direction != dir && buf->direction != DMA_BIDIRECTIONAL); dev_dbg(dev, "%s: unsafe buffer %p (dma=%#x off=%#lx) mapped to %p (dma=%#x)\n", __func__, buf->ptr, virt_to_dma(dev, buf->ptr), off,
This is equivalent of a more generic change to lib/dma-debug.c which is present since v2.6.33: commit 42d53b4ff7d61487d18274ebdf1f70c1aef6f122 dma-debug: allow DMA_BIDIRECTIONAL mappings to be synced with DMA_FROM_DEVICE and DMA_TO_DEVICE. There is no need to perform full BIDIR sync (copying the buffers in case of swiotlb and similar schemes) if we know that the owner (CPU or device) hasn't altered the data. Addresses the false-positive reported at http://bugzilla.kernel.org/show_bug.cgi?id=14169 Signed-off-by: Krzysztof Hałasa <khc@pm.waw.pl>