mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/
synced 2026-10-16 22:39:48 +00:00
No description
- C 96.9%
- Assembly 0.9%
- Rust 0.6%
- Shell 0.6%
- Python 0.5%
- Other 0.3%
59bf3557cf
Calculate the appropriate mask for non-size-aligned page selective
invalidation. Since psi uses the mask value to mask out the lower order
bits of the target address, properly flushing the iotlb requires using a
mask value such that [pfn, pfn+pages) all lie within the flushed
size-aligned region. This is not normally an issue because iova.c
always allocates iovas that are aligned to their size. However, iovas
which come from other sources (e.g. userspace via VFIO) may not be
aligned.
To properly flush the IOTLB, both the start and end pfns need to be
equal after applying the mask. That means that the most efficient mask
to use is the index of the lowest bit that is equal where all higher
bits are also equal. For example, if pfn=0x17f and pages=3, then
end_pfn=0x181, so the smallest mask we can use is 8. Any differences
above the highest bit of pages are due to carrying, so by xnor'ing pfn
and end_pfn and then masking out the lower order bits based on pages, we
get 0xffffff00, where the first set bit is the mask we want to use.
Fixes:
|
History
|
|
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
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.