tree db1412e9ed65e00f7189a623f9c48130aadc369c
parent 677a3baba4356b91c7acfb5828dd9a598decda6a
author Jingqi Liu <jingqi.liu@intel.com> 1588150211 +0800
committer Paolo Bonzini <pbonzini@redhat.com> 1593168331 -0400

configure: add libdaxctl support

Add a pair of configure options --{enable,disable}-libdaxctl to control
whether QEMU is compiled with libdaxctl [1]. Libdaxctl is a utility
library for managing the device dax subsystem.

QEMU uses mmap(2) to maps vNVDIMM backends and aligns the mapping
address to the page size (getpagesize(2)) by default. However, some
types of backends may require an alignment different than the page
size. The 'align' option is provided to memory-backend-file to allow
users to specify the proper alignment.

For device dax (e.g., /dev/dax0.0), the 'align' option needs to match
the alignment requirement of the device dax, which can be fetched
through the APIs of libdaxctl version 57 or up.

[1] Libdaxctl is a part of ndctl project.
The project's repository is: https://github.com/pmem/ndctl

For more information about libdaxctl APIs, you can refer to the
comments in source code of: pmem/ndctl/daxctl/lib/libdaxctl.c.

Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Jingqi Liu <jingqi.liu@intel.com>
Message-Id: <20200429085011.63752-4-jingqi.liu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>