Re: [PATCH v2] 9pfs: Add FreeBSD support

[Christian Schoenebeck <qemu_oss@crudebyte.com>]

On Wednesday, August 6, 2025 7:53:08 PM CEST Mark Johnston wrote:
> This is largely derived from existing Darwin support.  FreeBSD
> apparently has better support for *at() system calls so doesn't require
> workarounds for a missing mknodat().  The implementation has a couple of
> warts however:
> - The extattr(2) system calls don't support anything akin to
>   XATTR_CREATE or XATTR_REPLACE, so a racy workaround is implemented.
> - Attribute names cannot begin with "user." on ZFS, so the prefix is
>   trimmed off.  FreeBSD's extattr system calls sport an extra
>   "namespace" identifier, and attributes created by the 9pfs backend
>   live in the universal user namespace, so this seems innocent enough.
> 
> The 9pfs tests were verified to pass on the UFS, ZFS and tmpfs
> filesystems.
> 
> Signed-off-by: Mark Johnston <markj@FreeBSD.org>
> ---
> Changes since v1:
> - Handle extended attributes in the system.* namespace as well.
> - Fix a typo in a comment.
> - Clarify a comment.

Not forgotten. I just hoped there were other reviewers or testers in the 
meantime, but be it.

Like I said, I don't have FreeBSD system here to test this, so I am taking 
your word for now that you tested this and plan to bring this into QEMU when 
master re-opens for new features soon.

If you have some time to adjust the commit log message above, that would be 
great, otherwise I can also handle this on my end later on. Looks like that 
comment is not adjusted for v2 yet (i.e. "user." and not mentioning 
"system.").

/Christian