diff options
| author | Logan Gunthorpe <logang@deltatee.com> | 2017-12-18 11:25:06 -0700 |
|---|---|---|
| committer | Jon Mason <jdmason@kudzu.us> | 2018-01-28 22:17:23 -0500 |
| commit | 1e2fd202f8593985cdadca32e0c322f98e7fe7cb (patch) | |
| tree | 7311dd34491422541cc82c44d20ac2c98ac9058e /drivers/ntb | |
| parent | cbd27448faff4843ac4b66cc71445a10623ff48d (diff) | |
| download | lwn-1e2fd202f8593985cdadca32e0c322f98e7fe7cb.tar.gz lwn-1e2fd202f8593985cdadca32e0c322f98e7fe7cb.zip | |
ntb_hw_switchtec: Check for alignment of the buffer in mw_set_trans()
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>
Diffstat (limited to 'drivers/ntb')
| -rw-r--r-- | drivers/ntb/hw/mscc/ntb_hw_switchtec.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/drivers/ntb/hw/mscc/ntb_hw_switchtec.c b/drivers/ntb/hw/mscc/ntb_hw_switchtec.c index bcd5b6fb3800..6c6f991999b5 100644 --- a/drivers/ntb/hw/mscc/ntb_hw_switchtec.c +++ b/drivers/ntb/hw/mscc/ntb_hw_switchtec.c @@ -320,6 +320,19 @@ static int switchtec_ntb_mw_set_trans(struct ntb_dev *ntb, int pidx, int widx, 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) |