From: Bart Van Assche <bvanassche@xxxxxxx> [ Upstream commit c9121262d57b8a3be4f08073546436ba0128ca6a ] The dma_set_max_seg_size() call in setup_dma_device() does not have any effect since device->dev.dma_parms is NULL. Fix this by initializing device->dev.dma_parms first. Link: https://lore.kernel.org/r/20191025225830.257535-5-bvanassche@xxxxxxx Fixes: d10bcf947a3e ("RDMA/umem: Combine contiguous PAGE_SIZE regions in SGEs") Signed-off-by: Bart Van Assche <bvanassche@xxxxxxx> Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx> Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/infiniband/core/device.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/drivers/infiniband/core/device.c b/drivers/infiniband/core/device.c index 50a92442c4f7c..e6327d8f5b79a 100644 --- a/drivers/infiniband/core/device.c +++ b/drivers/infiniband/core/device.c @@ -1199,9 +1199,21 @@ static void setup_dma_device(struct ib_device *device) WARN_ON_ONCE(!parent); device->dma_device = parent; } - /* Setup default max segment size for all IB devices */ - dma_set_max_seg_size(device->dma_device, SZ_2G); + if (!device->dev.dma_parms) { + if (parent) { + /* + * The caller did not provide DMA parameters, so + * 'parent' probably represents a PCI device. The PCI + * core sets the maximum segment size to 64 + * KB. Increase this parameter to 2 GB. + */ + device->dev.dma_parms = parent->dma_parms; + dma_set_max_seg_size(device->dma_device, SZ_2G); + } else { + WARN_ON_ONCE(true); + } + } } /* -- 2.20.1
