support for mknod to windows now in cifs vfs
smfrench at austin.rr.com
Sat Nov 19 19:55:37 GMT 2005
Andrew Bartlett wrote:
>On Fri, 2005-11-18 at 22:30 -0600, Steve French wrote:
>>I added the code to cifs vfs to enable it do mknod of block and
>>chardevice even if the server does not support the Unix extensions (such
>>as Windows). This requires the "sfu" mount option to be specified
>Any reason why this isn't on by default?
I agree with most of Martin's points - even on Windows there are a few
(possibly with Vista) three ways e.g. to do symlinks. Although sfu is
the most important way to do it it is a bit slower too.
The "sfu" mount option (services for Unix) is not turned on by default
on mounts from cifs vfs to Windows servers (and servers which unlike
Samba do not support the CIFS Unix/POSIX extensions) because it is
Checking the mode bits requires:
1) An extra roundtrip on each lookup for query of an Extended Attributed
(xattr) for the top 3 bits of the mode and eventually an extra one
beyond that for getting the security descriptor (for the bottom nine
bits, 0777 part, of the mode). This would be particularly expensive on
2) An extra read for every non-empty file marked with the "system"
attribute (dos attribute) to see if the file begins with a signature
indicating (block, char or symlink)
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