From owner-freebsd-questions  Thu Nov 22  1:27:22 2001
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From: "XuYifeng" <xuyifeng@peoplemail.com.cn>
To: <freebsd-questions@freebsd.org>
Subject: vm_uiomove() help
Date: Thu, 22 Nov 2001 17:23:27 +0800
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Hi,

I am studying FreeBSD vm source code, currently I am blocked by
vm_uiomove() in vm_map.c, could anyone tell me why we need=20
following lines to determine if it the first_object was not replaced:

    if ((first_object->type =3D=3D OBJT_VNODE) &&
        ((oldobject =3D entry->object.vm_object) =3D=3D first_object))

I see vm_map_clip_start{end} don't replace object within that entry,
so ((oldobject =3D entry->object.vm_object) =3D=3D first_object) is =
needn't,
am I wrong?

--
Regards,
David Xu




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