Re: [PATCH 0/3] Adding offset keeping option when mapping data via SWIOTLB.*

[Greg KH]

On Wed, Jan 27, 2021 at 04:38:26PM -0800, Jianxiong Gao wrote:
> NVMe driver and other applications may depend on the data offset
> to operate correctly. Currently when unaligned data is mapped via
> SWIOTLB, the data is mapped as slab aligned with the SWIOTLB. This
> patch adds an option to make sure the mapped data preserves its
> offset of the orginal addrss.
> 
> Without the patch when creating xfs formatted disk on NVMe backends,
> with swiotlb=force in kernel boot option, creates the following error:
> meta-data=/dev/nvme2n1           isize=512    agcount=4, agsize=131072 blks
>          =                       sectsz=512   attr=2, projid32bit=1
>          =                       crc=1        finobt=1, sparse=0, rmapbt=0, refl
> ink=0
> data     =                       bsize=4096   blocks=524288, imaxpct=25
>          =                       sunit=0      swidth=0 blks
> naming   =version 2              bsize=4096   ascii-ci=0 ftype=1
> log      =internal log           bsize=4096   blocks=2560, version=2
>          =                       sectsz=512   sunit=0 blks, lazy-count=1
> realtime =none                   extsz=4096   blocks=0, rtextents=0
> mkfs.xfs: pwrite failed: Input/output error
> 
> Jianxiong Gao (3):
>   Adding page_offset_mask to device_dma_parameters
>   Add swiotlb offset preserving mapping when
>     dma_dma_parameters->page_offset_mask is non zero.
>   Adding device_dma_parameters->offset_preserve_mask to NVMe driver.


Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
a patch that has triggered this response.  He used to manually respond
to these common problems, but in order to save his sanity (he kept
writing the same thing over and over, yet to different people), I was
created.  Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.

You are receiving this message because of the following common error(s)
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