Re: [Qemu-devel] [PATCH] linux-user EFAULT implementation

[Stuart Anderson <anderson@netsweng.com>]

On Fri, 6 Jul 2007, Stuart Anderson wrote:

> So, the question is:
>
> 	Can I simplify this code to assume that guest and
> 	host addresses coexist and use the copy_*_user() or
> 	just the access_ok() interfaces?

Attached is a diff that shows what this will look like for the struct
sockaddr handling case. In short, the two functions for mapping this
structure get renamed

 	target_to_host_sockaddr -> copy_from_user_sockaddr
 	host_to_target_sockaddr -> copy_to_user_sockaddr

and lose the pg_access parameter as read/write access is determined
by wether we are copying to or from "user space". The macro access_ok()
is used to check the validity of the memory being accessed.

This change also completely drops the notion of locking and unlocking memory,
which was the previous model being used.

Fabrice,

Is this change what you had in mind? Does it cause a problem for anyone
else?



                                 Stuart

Stuart R. Anderson                               anderson@netsweng.com
Network & Software Engineering                   http://www.netsweng.com/
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