IB/hfi1: Fix user context tail allocation for DMA_RTAIL
The following code fails to allocate a buffer for the
tail address that the hardware DMAs into when the user
context DMA_RTAIL is set.
if (HFI1_CAP_KGET_MASK(rcd->flags, DMA_RTAIL)) {
rcd->rcvhdrtail_kvaddr = dma_zalloc_coherent(
&dd->pcidev->dev, PAGE_SIZE, &dma_hdrqtail,
gfp_flags);
if (!rcd->rcvhdrtail_kvaddr)
goto bail_free;
rcd->rcvhdrqtailaddr_dma = dma_hdrqtail;
}
So the rcvhdrtail_kvaddr would then be NULL.
The mmap logic fails to check for a NULL rcvhdrtail_kvaddr.
The fix is to test for both user and kernel DMA_TAIL options
during the allocation as well as testing for a NULL
rcvhdrtail_kvaddr during the mmap processing.
Additionally, all downstream testing of the capmask for DMA_RTAIL
have been eliminated in favor of testing rcvhdrtail_kvaddr.
Cc: <stable@vger.kernel.org> # 4.9.x Reviewed-by: Michael J. Ruhl <michael.j.ruhl@intel.com> Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com> Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>