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5d95f40e62
The original motivation for iommu_map_sg() was to give IOMMU drivers the chance to map an IOVA-contiguous scatterlist as efficiently as they could. It turns out that there isn't really much driver-specific business involved there, so now that the default implementation is mandatory let's just improve that - the main thing we're after is to use larger pages wherever possible, and as long as domain->pgsize_bitmap reflects reality, iommu_map() can already do that in a generic way. All we need to do is detect physically-contiguous segments and batch them into a single map operation, since whatever we do here is transparent to our caller and not bound by any segment-length restrictions on the list itself. Speaking of efficiency, there's really very little point in duplicating the checks that iommu_map() is going to do anyway, so those get cleared up in the process. Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Joerg Roedel <jroedel@suse.de>
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.