hostmem-memfd: honour share=on/off property

The share=on/off property is used to modified mmap() MAP_SHARED
setting. Make it on by default for convenience and compatibility
reasons.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Marc-André Lureau 2018-08-28 17:38:40 +02:00 committed by Paolo Bonzini
parent 15ffb43cbf
commit 36ea397956
2 changed files with 6 additions and 2 deletions

View File

@ -59,7 +59,8 @@ memfd_backend_memory_alloc(HostMemoryBackend *backend, Error **errp)
name = object_get_canonical_path(OBJECT(backend));
memory_region_init_ram_from_fd(&backend->mr, OBJECT(backend),
name, backend->size, true, fd, errp);
name, backend->size,
backend->share, fd, errp);
g_free(name);
}
@ -131,6 +132,7 @@ memfd_backend_instance_init(Object *obj)
/* default to sealed file */
m->seal = true;
MEMORY_BACKEND(m)->share = true;
}
static void

View File

@ -4025,7 +4025,7 @@ Memory backend objects offer more control than the @option{-m} option that is
traditionally used to define guest RAM. Please refer to
@option{memory-backend-file} for a description of the options.
@item -object memory-backend-memfd,id=@var{id},merge=@var{on|off},dump=@var{on|off},prealloc=@var{on|off},size=@var{size},host-nodes=@var{host-nodes},policy=@var{default|preferred|bind|interleave},seal=@var{on|off},hugetlb=@var{on|off},hugetlbsize=@var{size}
@item -object memory-backend-memfd,id=@var{id},merge=@var{on|off},dump=@var{on|off},share=@var{on|off},prealloc=@var{on|off},size=@var{size},host-nodes=@var{host-nodes},policy=@var{default|preferred|bind|interleave},seal=@var{on|off},hugetlb=@var{on|off},hugetlbsize=@var{size}
Creates an anonymous memory file backend object, which allows QEMU to
share the memory with an external process (e.g. when using
@ -4047,6 +4047,8 @@ with the @option{seal} option (requires at least Linux 4.16).
Please refer to @option{memory-backend-file} for a description of the
other options.
The @option{share} boolean option is @var{on} by default with memfd.
@item -object rng-random,id=@var{id},filename=@var{/dev/random}
Creates a random number generator backend which obtains entropy from