The core of the patch - allow the last sg element in a scatterlist
table to point to the start of a new table. We overload the LSB of
the page pointer to indicate whether this is a valid sg entry, or
merely a link to the next list.
Includes a fix from Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
correcting the ifdef ARCH_HAS_SG_CHAIN guarding sg_last().
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This patch adds a const modifier to the buf argument of sg_set_buf and
sg_init_one. This lets people call it with pointers that are const.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
sg_init_one is a nice tool for the block layer. However, users
of struct scatterlist in other subsystems don't usually need the
DMA attributes. For them it's a waste of time and space to
initialise the whole struct scatterlist structure.
Therefore this patch adds a new function sg_set_buf to initialise
a scatterlist without zeroing the DMA attributes.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Jens Axboe