This patch series improves choosing reparse format when creating new
special files.
In following table is behavior of creating new special files before
this patch series. In columns are mount options, in rows are file types
and in each cell is reparse format which is created.
-o reparse=default -o reparse=nfs -o reparse=wsl
symlink native native native
socket nfs nfs wsl
fifo nfs nfs wsl
block nfs nfs wsl
char nfs nfs wsl
After this patch series the table looks like:
-o reparse=default -o reparse=nfs -o reparse=wsl -o reparse=native+nfs -o reparse=native+wsl -o reparse=native -o reparse=none
symlink native nfs wsl native native native -disallowed-
socket native nfs wsl native native native -disallowed-
fifo nfs nfs wsl nfs wsl -disallowed- -disallowed-
block nfs nfs wsl nfs wsl -disallowed- -disallowed-
char nfs nfs wsl nfs wsl -disallowed- -disallowed-
The default behavior when no option is specified (which is same as
-o reparse=default) changes only for creating new sockets which are
now created in its native NTFS form with IO_REPARSE_TAG_AF_UNIX reparse
tag.
The nfs and wsl behavior is changed to always create new special files
in its own formats.
There are new options native+nfs and native+wsl which creates by default
in native form (symlinks + sockets) and fallbacks to nfs/wsl for other
types (fifo, char, block). This is probably the most useful for
interoperability. Mount option -o reparse=default is now same as
-o reparse=native+nfs
For completeness there are also new options -o reparse=native which
allows to creating only native types used by Windows applications
(symlinks and sockets) and option -o reparse=none to completely disable
creating new reparse points.
Pali Rohár (7):
cifs: Add mount option -o reparse=native
cifs: Add mount option -o reparse=none
cifs: Add support for creating native Windows sockets
cifs: Add support for creating NFS-style symlinks
cifs: Improve guard for excluding $LXDEV xattr
cifs: Add support for creating WSL-style symlinks
cifs: Validate content of WSL reparse point buffers
fs/smb/client/cifsglob.h | 18 +++-
fs/smb/client/fs_context.c | 16 +++
fs/smb/client/fs_context.h | 4 +
fs/smb/client/reparse.c | 211 +++++++++++++++++++++++++++++++------
fs/smb/client/reparse.h | 2 +
5 files changed, 218 insertions(+), 33 deletions(-)
--
2.20.1
