Re: [PATCH 1/7] cifs: Add mount option -o reparse=native

[Steve French]

On Thu, Oct 10, 2024 at 5:17 PM Steve French <smfrench@xxxxxxxxx> wrote:
>
>
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> On Mon, Oct 7, 2024 at 1:36 PM Pali Rohár <pali@xxxxxxxxxx> wrote:
>>
>> Currently choosing how new symlinks are created is quite complicated.
>>
>> Without these patch series, by default new symlinks are created via
>> native reparse points, even when reparse=nfs or reparse=wsl is
>> specified. There is no possibility to create a NFS-style or WSL-style
>> symlink yet, and this patch series address this missing functionality.
>> When option -o sfu is specified then all new symlinks are created in
>> SFU-style, independently of -o reparse option. And when -o mfsymlinks is
>> specified then all new symlinks are created in mf style, independently
>> of -o reparse and -o sfu options.
>>
>> This patch series does not change -o sfu and -o mfsymlinks overrides, it
>> just changes the way how -o reparse is handled.
>>

I lean toward something similar, and more intuitive - do not have
"reparse=" control symlink creation - but instead use another mount
parm (e.g. "symlink=") for that.  It would be rarely used - only if
you don't want the default (windows default format too) for server
symlinks or "mfsymlinks" (for client only symlinks):

1) "symlink=" if specified can be set to one of five formats (with the
default being the windows format)
  a) "mfsymlinks" (Mac style which is safer for many use cases since
they are "client only" symlinks which the server will never use)
     Setting "symlink=mfsymlinks" will have the same effect as just
specifying "mfsymlinks" so won't break anything
  b) "default" (or "windows") which uses the default symlink format
when trying to create a new symlink
  c) "nfs"
  d) "wsl"
  e) "sfu"
2) "reparse=" will still control how special files are created (char,
block, fifo, socket) and can be set to:
   a) "nfs" (default)
   b) or "wsl"
   c) If "sfu" set on mount will cause special files to be created
with "sfu" format instead of using reparse points to create
3) reading reparse points will always be supported (unless you want to
add a new parameter "reparse=none" to treat all reparse points as
empty directories)
4) reading special files via the old "sfu" will only be supported if
you mount with "sfu"




-- 
Thanks,

Steve