7e9c7ef83d
Create a sysfs bin attribute called "allocate" under the existing "p2pmem" group. The only allowable operation on this file is the mmap() call. When mmap() is called on this attribute, the kernel allocates a chunk of memory from the genalloc and inserts the pages into the VMA. The dev_pagemap .page_free callback will indicate when these pages are no longer used and they will be put back into the genalloc. On device unbind, remove the sysfs file before the memremap_pages are cleaned up. This ensures unmap_mapping_range() is called on the files inode and no new mappings can be created. Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com> Link: https://lore.kernel.org/r/20221021174116.7200-9-logang@deltatee.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
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.