mainlining shenanigans
1ab5b82f54
With hugetlbfs, a common pattern for mapping anonymous huge pages is to create a temporary file first. Currently libraries like libhugetlbfs and seastar create these with a standard mkstemp+unlink trick, but it would be more robust to be able to simply pass the O_TMPFILE flag to open(). O_TMPFILE is already supported by several file systems like ext4 and xfs. The implementation simply uses the existi= ng d_tmpfile utility function to instantiate the dcache entry for the file. Tested manually by successfully creating a temporary file by opening it with (O_TMPFILE|O_RDWR) on mounted hugetlbfs and successfully mapping 2M huge pages with it. Without the patch, trying to open a file with O_TMPFILE results in -ENOSUP. Link: http://lkml.kernel.org/r/bc9383eff6e1374d79f3a92257ae829ba1e6ae60.1573285189.git.p.sarna@tlen.pl Signed-off-by: Piotr Sarna <p.sarna@tlen.pl> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Michal Hocko <mhocko@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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| 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.