[CIFS] Add compat with SFU (part 1)

This should help the case of creating fifos and other special files to
servers which do not support the Unix extensions.

Signed-off-by: Steve French (sfrench@us.ibm.com)

Thanks to Martin Koeppe for his suggestions and good analysis

3 files changed, 19 insertions, 1 deletions

diff --git a/fs/cifs/cifs_fs_sb.h b/fs/cifs/cifs_fs_sb.h
index 5dc5fe6b486d..6b93587c490e 100644
--- a/fs/cifs/cifs_fs_sb.h
+++ b/fs/cifs/cifs_fs_sb.h
@@ -25,6 +25,7 @@
 #define CIFS_MOUNT_NO_XATTR  0x10 /* if set - disable xattr support */
 #define CIFS_MOUNT_MAP_SPECIAL_CHR 0x20 /* remap illegal chars in filenames */
 #define CIFS_MOUNT_POSIX_PATHS 0x40 /* Negotiate posix pathnames if possible. */
+#define CIFS_MOUNT_UNX_EMUL    0x80 /* Network compat with SFUnix emulation */
 
 struct cifs_sb_info {
         struct cifsTconInfo *tcon;      /* primary mount */
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index f6d2a7974fc1..36f78596c81a 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -75,6 +75,7 @@ struct smb_vol {
         unsigned direct_io:1;
         unsigned remap:1;   /* set to remap seven reserved chars in filenames */
         unsigned posix_paths:1;   /* unset to not ask for posix pathnames. */
+        unsigned sfu_emul:1;
         unsigned int rsize;
         unsigned int wsize;
         unsigned int sockopt;
@@ -1027,6 +1028,10 @@ cifs_parse_mount_options(char *options, const char *devname,struct smb_vol *vol)
                         vol->remap = 1;
                 } else if (strnicmp(data, "nomapchars", 10) == 0) {
                         vol->remap = 0;
+                } else if (strnicmp(data, "sfu", 3) == 0) {
+                        vol->sfu_emul = 1;
+                } else if (strnicmp(data, "nosfu", 5) == 0) {
+                        vol->sfu_emul = 0;
                 } else if (strnicmp(data, "posixpaths", 10) == 0) {
                         vol->posix_paths = 1;
                 } else if (strnicmp(data, "noposixpaths", 12) == 0) {
@@ -1687,6 +1692,8 @@ cifs_mount(struct super_block *sb, struct cifs_sb_info *cifs_sb,
                         cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_MAP_SPECIAL_CHR;
                 if(volume_info.no_xattr)
                         cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NO_XATTR;
+                if(volume_info.sfu_emul)
+                        cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_UNX_EMUL;
 
                 if(volume_info.direct_io) {
                         cERROR(1,("mounting share using direct i/o"));
diff --git a/fs/cifs/dir.c b/fs/cifs/dir.c
index 9360d8fb9ef7..0d5e27fec92b 100644
--- a/fs/cifs/dir.c
+++ b/fs/cifs/dir.c
@@ -209,7 +209,7 @@ cifs_create(struct inode *inode, struct dentry *direntry, int mode,
                                                 CIFS_MOUNT_MAP_SPECIAL_CHR);
                         }
                 else {
-                        /* BB implement via Windows security descriptors */
+                        /* BB implement mode setting via Windows security descriptors */
                         /* eg CIFSSMBWinSetPerms(xid,pTcon,full_path,mode,-1,-1,local_nls);*/
                         /* could set r/o dos attribute if mode & 0222 == 0 */
                 }
@@ -326,6 +326,16 @@ int cifs_mknod(struct inode *inode, struct dentry *direntry, int mode, dev_t dev
                         if(rc == 0)
                                 d_instantiate(direntry, newinode);
                 }
+        } else {
+                if((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL) && 
+                        (special_file(mode))) {
+
+                        cFYI(1,("sfu compat create special file"));
+                        /*      Attributes = cpu_to_le32(ATTR_SYSTEM); 
+                                rc = CIFSSMBOpen(xid, pTcon, full_path, disposition, ...); */
+
+                        /* add code here to set EAs */
+                }
         }
 
         kfree(full_path);