d10bcf947a
Combine contiguous regions of PAGE_SIZE pages into single scatter list entry while building the scatter table for a umem. This minimizes the number of the entries in the scatter list and reduces the DMA mapping overhead, particularly with the IOMMU. Set default max_seg_size in core for IB devices to 2G and do not combine if we exceed this limit. Also, purge npages in struct ib_umem as we now DMA map the umem SGL with sg_nents and npage computation is not needed. Drivers should now be using ib_umem_num_pages(), so fix the last stragglers. Move npages tracking to ib_umem_odp as ODP drivers still need it. Suggested-by: Jason Gunthorpe <jgg@ziepe.ca> Reviewed-by: Michael J. Ruhl <michael.j.ruhl@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Acked-by: Adit Ranadive <aditr@vmware.com> Signed-off-by: Shiraz Saleem <shiraz.saleem@intel.com> Tested-by: Gal Pressman <galpress@amazon.com> Tested-by: Selvin Xavier <selvin.xavier@broadcom.com> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.