[PATCH RFC 0/2] scatterlist: add I/O variant of sg_pcopy & sg_copy and use them

[Neil Armstrong]

A local variant of sg_copy_buffer has been introduced in the meson-gx mmc driver [1] after
a mempcy optimization, fixing the iomem buffer manipulation and the reported system crash [2].

But, the fix is suboptimal in terms of performace/ugliness [3] and a proper I/O variant of
sg_copy_buffer should be added and used instead.

[1] https://lore.kernel.org/r/20210609150230.9291-1-narmstrong@baylibre.com
[2] https://lore.kernel.org/r/acb244ad-0759-5a96-c659-5c23003d3dcd@samsung.com
[3] https://lore.kernel.org/r/CAPDyKFrLSMpPJOgd5e4B1x3Vwfg4q23zgy4ESc8EmFL2MnyK7g@mail.gmail.com

Neil Armstrong (2):
  scatterlist: add I/O variant of sg_pcopy & sg_copy
  mmc: meson-gx: use sg_copy_to/from_io instead of local version

 drivers/mmc/host/meson-gx-mmc.c |  53 +++-----------
 include/linux/scatterlist.h     |  14 ++++
 lib/scatterlist.c               | 119 ++++++++++++++++++++++++++++++++
 3 files changed, 143 insertions(+), 43 deletions(-)

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2.25.1