With Switchtec hardware, the buffer used for a memory window must be
aligned to its size (the hardware only replaces the lower bits). In
certain circumstances dma_alloc_coherent() will not provide a buffer
that adheres to this requirement like when using the CMA and
CONFIG_CMA_ALIGNMENT is set lower than the buffer size.
When we get an unaligned buffer mw_set_trans() should return an error.
We also log an error so we know the cause of the problem.
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
if (xlate_pos < 12)
return -EINVAL;
+ if (!IS_ALIGNED(addr, BIT_ULL(xlate_pos))) {
+ /*
+ * In certain circumstances we can get a buffer that is
+ * not aligned to its size. (Most of the time
+ * dma_alloc_coherent ensures this). This can happen when
+ * using large buffers allocated by the CMA
+ * (see CMA_CONFIG_ALIGNMENT)
+ */
+ dev_err(&sndev->stdev->dev,
+ "ERROR: Memory window address is not aligned to it's size!\n");
+ return -EINVAL;
+ }
+
rc = switchtec_ntb_part_op(sndev, ctl, NTB_CTRL_PART_OP_LOCK,
NTB_CTRL_PART_STATUS_LOCKED);
if (rc)