smb: client: set correct file type from NFS reparse points

Handle all file types in NFS reparse points as specified in MS-FSCC
2.1.2.6 Network File System (NFS) Reparse Data Buffer.

The client is now able to set all file types based on the parsed NFS
reparse point, which used to support only symlinks.  This works for
SMB1+.

Before patch:

$ mount.cifs //srv/share /mnt -o ...
$ ls -l /mnt
ls: cannot access 'block': Operation not supported
ls: cannot access 'char': Operation not supported
ls: cannot access 'fifo': Operation not supported
ls: cannot access 'sock': Operation not supported
total 1
l????????? ? ?    ?    ?            ? block
l????????? ? ?    ?    ?            ? char
-rwxr-xr-x 1 root root 5 Nov 18 23:22 f0
l????????? ? ?    ?    ?            ? fifo
l--------- 1 root root 0 Nov 18 23:23 link -> f0
l????????? ? ?    ?    ?            ? sock

After patch:

$ mount.cifs //srv/share /mnt -o ...
$ ls -l /mnt
total 1
brwxr-xr-x 1 root root  123,  123 Nov 18 00:34 block
crwxr-xr-x 1 root root 1234, 1234 Nov 18 00:33 char
-rwxr-xr-x 1 root root          5 Nov 18 23:22 f0
prwxr-xr-x 1 root root          0 Nov 18 23:23 fifo
lrwxr-xr-x 1 root root          0 Nov 18 23:23 link -> f0
srwxr-xr-x 1 root root          0 Nov 19  2023 sock

Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>

1 files changed, 7 insertions, 1 deletions

diff --git a/fs/smb/client/cifsglob.h b/fs/smb/client/cifsglob.h
index 111daa4ff261..7558167f603c 100644
--- a/fs/smb/client/cifsglob.h
+++ b/fs/smb/client/cifsglob.h
@@ -191,7 +191,13 @@ struct cifs_open_info_data {
 		bool reparse_point;
 		bool symlink;
 	};
-	__u32 reparse_tag;
+	struct {
+		__u32 tag;
+		union {
+			struct reparse_data_buffer *buf;
+			struct reparse_posix_data *posix;
+		};
+	} reparse;
 	char *symlink_target;
 	union {
 		struct smb2_file_all_info fi;