[CIFS] UID/GID override on CIFS mounts to Samba

When CIFS Unix Extensions are negotiated we get the Unix uid and gid
owners of the file from the server (on the Unix Query Path Info
levels), but if the server's uids don't match the client uid's users
were having to disable the Unix Extensions (which turned off features
they still wanted).   The changeset patch allows users to override uid
and/or gid for file/directory owner with a default uid and/or gid
specified at mount (as is often done when mounting from Linux cifs
client to Windows server).  This changeset also displays the uid
and gid used by default in /proc/mounts (if applicable).

Also cleans up code by adding some of the missing spaces after
"if" keywords per-kernel style guidelines (as suggested by Randy Dunlap
when he reviewed the patch).

Signed-off-by: Steve French <sfrench@us.ibm.com>

1 files changed, 33 insertions, 22 deletions

diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index f74f37cee119..3e87dad3367c 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -90,7 +90,7 @@ int cifs_get_inode_info_unix(struct inode **pinode,
                                 (*pinode)->i_ino =
                                         (unsigned long)findData.UniqueId;
                         } /* note ino incremented to unique num in new_inode */
-                        if(sb->s_flags & MS_NOATIME)
+                        if (sb->s_flags & MS_NOATIME)
                                 (*pinode)->i_flags |= S_NOATIME | S_NOCMTIME;
                                 
                         insert_inode_hash(*pinode);
@@ -139,8 +139,17 @@ int cifs_get_inode_info_unix(struct inode **pinode,
                         inode->i_mode |= S_IFREG;
                         cFYI(1,("unknown type %d",type));
                 }
-                inode->i_uid = le64_to_cpu(findData.Uid);
-                inode->i_gid = le64_to_cpu(findData.Gid);
+                
+                if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_OVERR_UID)
+                        inode->i_uid = cifs_sb->mnt_uid;
+                else
+                        inode->i_uid = le64_to_cpu(findData.Uid);
+
+                if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_OVERR_GID)
+                        inode->i_gid = cifs_sb->mnt_gid;
+                else
+                        inode->i_gid = le64_to_cpu(findData.Gid);
+                        
                 inode->i_nlink = le64_to_cpu(findData.Nlinks);
 
                 spin_lock(&inode->i_lock);
@@ -178,13 +187,13 @@ int cifs_get_inode_info_unix(struct inode **pinode,
                                                 &cifs_file_direct_nobrl_ops;
                                 else
                                         inode->i_fop = &cifs_file_direct_ops;
-                        } else if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
+                        } else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
                                 inode->i_fop = &cifs_file_nobrl_ops;
                         else /* not direct, send byte range locks */ 
                                 inode->i_fop = &cifs_file_ops;
 
                         /* check if server can support readpages */
-                        if(pTcon->ses->server->maxBuf < 
+                        if (pTcon->ses->server->maxBuf < 
                             PAGE_CACHE_SIZE + MAX_CIFS_HDR_SIZE)
                                 inode->i_data.a_ops = &cifs_addr_ops_smallbuf;
                         else
@@ -220,7 +229,7 @@ static int decode_sfu_inode(struct inode * inode, __u64 size,
 
         pbuf = buf;
 
-        if(size == 0) {
+        if (size == 0) {
                 inode->i_mode |= S_IFIFO;
                 return 0;
         } else if (size < 8) {
@@ -239,11 +248,11 @@ static int decode_sfu_inode(struct inode * inode, __u64 size,
                                  netfid,
                                  24 /* length */, 0 /* offset */,
                                  &bytes_read, &pbuf, &buf_type);
-                if((rc == 0) && (bytes_read >= 8)) {
-                        if(memcmp("IntxBLK", pbuf, 8) == 0) {
+                if ((rc == 0) && (bytes_read >= 8)) {
+                        if (memcmp("IntxBLK", pbuf, 8) == 0) {
                                 cFYI(1,("Block device"));
                                 inode->i_mode |= S_IFBLK;
-                                if(bytes_read == 24) {
+                                if (bytes_read == 24) {
                                         /* we have enough to decode dev num */
                                         __u64 mjr; /* major */
                                         __u64 mnr; /* minor */
@@ -251,10 +260,10 @@ static int decode_sfu_inode(struct inode * inode, __u64 size,
                                         mnr = le64_to_cpu(*(__le64 *)(pbuf+16));
                                         inode->i_rdev = MKDEV(mjr, mnr);
                                 }
-                        } else if(memcmp("IntxCHR", pbuf, 8) == 0) {
+                        } else if (memcmp("IntxCHR", pbuf, 8) == 0) {
                                 cFYI(1,("Char device"));
                                 inode->i_mode |= S_IFCHR;
-                                if(bytes_read == 24) {
+                                if (bytes_read == 24) {
                                         /* we have enough to decode dev num */
                                         __u64 mjr; /* major */
                                         __u64 mnr; /* minor */
@@ -262,7 +271,7 @@ static int decode_sfu_inode(struct inode * inode, __u64 size,
                                         mnr = le64_to_cpu(*(__le64 *)(pbuf+16));
                                         inode->i_rdev = MKDEV(mjr, mnr);
                                 }
-                        } else if(memcmp("IntxLNK", pbuf, 7) == 0) {
+                        } else if (memcmp("IntxLNK", pbuf, 7) == 0) {
                                 cFYI(1,("Symlink"));
                                 inode->i_mode |= S_IFLNK;
                         } else {
@@ -293,7 +302,7 @@ static int get_sfu_uid_mode(struct inode * inode,
         rc = CIFSSMBQueryEA(xid, cifs_sb->tcon, path, "SETFILEBITS",
                         ea_value, 4 /* size of buf */, cifs_sb->local_nls,
                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
-        if(rc < 0)
+        if (rc < 0)
                 return (int)rc;
         else if (rc > 3) {
                 mode = le32_to_cpu(*((__le32 *)ea_value));
@@ -348,7 +357,7 @@ int cifs_get_inode_info(struct inode **pinode,
                 /* BB optimize code so we do not make the above call
                 when server claims no NT SMB support and the above call
                 failed at least once - set flag in tcon or mount */
-                if((rc == -EOPNOTSUPP) || (rc == -EINVAL)) {
+                if ((rc == -EOPNOTSUPP) || (rc == -EINVAL)) {
                         rc = SMBQueryInformation(xid, pTcon, search_path,
                                         pfindData, cifs_sb->local_nls, 
                                         cifs_sb->mnt_cifs_flags &
@@ -425,7 +434,7 @@ int cifs_get_inode_info(struct inode **pinode,
                                 } else /* do we need cast or hash to ino? */
                                         (*pinode)->i_ino = inode_num;
                         } /* else ino incremented to unique num in new_inode*/
-                        if(sb->s_flags & MS_NOATIME)
+                        if (sb->s_flags & MS_NOATIME)
                                 (*pinode)->i_flags |= S_NOATIME | S_NOCMTIME;
                         insert_inode_hash(*pinode);
                 }
@@ -442,7 +451,7 @@ int cifs_get_inode_info(struct inode **pinode,
                 (pTcon->ses->server->maxBuf - MAX_CIFS_HDR_SIZE) & 0xFFFFFE00;*/
 
                 /* Linux can not store file creation time so ignore it */
-                if(pfindData->LastAccessTime)
+                if (pfindData->LastAccessTime)
                         inode->i_atime = cifs_NTtimeToUnix
                                 (le64_to_cpu(pfindData->LastAccessTime));
                 else /* do not need to use current_fs_time - time not stored */
@@ -452,7 +461,7 @@ int cifs_get_inode_info(struct inode **pinode,
                 inode->i_ctime =
                     cifs_NTtimeToUnix(le64_to_cpu(pfindData->ChangeTime));
                 cFYI(0, ("Attributes came in as 0x%x", attr));
-                if(adjustTZ && (pTcon->ses) && (pTcon->ses->server)) {
+                if (adjustTZ && (pTcon->ses) && (pTcon->ses->server)) {
                         inode->i_ctime.tv_sec += pTcon->ses->server->timeAdj;
                         inode->i_mtime.tv_sec += pTcon->ses->server->timeAdj;
                 }
@@ -521,8 +530,10 @@ int cifs_get_inode_info(struct inode **pinode,
 
                 /* BB fill in uid and gid here? with help from winbind? 
                    or retrieve from NTFS stream extended attribute */
-                if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL) {
+                if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL) {
                         /* fill in uid, gid, mode from server ACL */
+                        /* BB FIXME this should also take into account the
+                         * default uid specified on mount if present */
                         get_sfu_uid_mode(inode, search_path, cifs_sb, xid);
                 } else if (atomic_read(&cifsInfo->inUse) == 0) {
                         inode->i_uid = cifs_sb->mnt_uid;
@@ -541,12 +552,12 @@ int cifs_get_inode_info(struct inode **pinode,
                                                 &cifs_file_direct_nobrl_ops;
                                 else
                                         inode->i_fop = &cifs_file_direct_ops;
-                        } else if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
+                        } else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
                                 inode->i_fop = &cifs_file_nobrl_ops;
                         else /* not direct, send byte range locks */
                                 inode->i_fop = &cifs_file_ops;
 
-                        if(pTcon->ses->server->maxBuf < 
+                        if (pTcon->ses->server->maxBuf < 
                              PAGE_CACHE_SIZE + MAX_CIFS_HDR_SIZE)
                                 inode->i_data.a_ops = &cifs_addr_ops_smallbuf;
                         else
@@ -597,7 +608,7 @@ int cifs_unlink(struct inode *inode, struct dentry *direntry)
 
         xid = GetXid();
 
-        if(inode)
+        if (inode)
                 cifs_sb = CIFS_SB(inode->i_sb);
         else
                 cifs_sb = CIFS_SB(direntry->d_sb);
@@ -723,7 +734,7 @@ int cifs_unlink(struct inode *inode, struct dentry *direntry)
                                            when needed */
                 direntry->d_inode->i_ctime = current_fs_time(inode->i_sb);
         }
-        if(inode) {
+        if (inode) {
                 inode->i_ctime = inode->i_mtime = current_fs_time(inode->i_sb);
                 cifsInode = CIFS_I(inode);
                 cifsInode->time = 0;    /* force revalidate of dir as well */