374c15594c
The io-pgtable code expects to operate on a single block or granule of memory that is supported by the IOMMU hardware when unmapping memory. This means that when a large buffer that consists of multiple such blocks is unmapped, the io-pgtable code will walk the page tables to the correct level to unmap each block, even for blocks that are virtually contiguous and at the same level, which can incur an overhead in performance. Introduce the unmap_pages() page table op to express to the io-pgtable code that it should unmap a number of blocks of the same size, instead of a single block. Doing so allows multiple blocks to be unmapped in one call to the io-pgtable code, reducing the number of page table walks, and indirect calls. Signed-off-by: Isaac J. Manjarres <isaacm@codeaurora.org> Suggested-by: Will Deacon <will@kernel.org> Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Georgi Djakov <quic_c_gdjako@quicinc.com> Link: https://lore.kernel.org/r/1623850736-389584-2-git-send-email-quic_c_gdjako@quicinc.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.