cifs: implement CIFSQueryMFSymLink()

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Steve French <sfrench@us.ibm.com>

1 files changed, 50 insertions, 0 deletions

diff --git a/fs/cifs/link.c b/fs/cifs/link.c
index bec212b09a02..6e4e8957595d 100644
--- a/fs/cifs/link.c
+++ b/fs/cifs/link.c
@@ -91,6 +91,56 @@ CIFSParseMFSymlink(const u8 *buf,
         return 0;
 }
 
+static int
+CIFSQueryMFSymLink(const int xid, struct cifsTconInfo *tcon,
+                   const unsigned char *searchName, char **symlinkinfo,
+                   const struct nls_table *nls_codepage, int remap)
+{
+        int rc;
+        int oplock = 0;
+        __u16 netfid = 0;
+        u8 *buf;
+        char *pbuf;
+        unsigned int bytes_read = 0;
+        int buf_type = CIFS_NO_BUFFER;
+        unsigned int link_len = 0;
+        FILE_ALL_INFO file_info;
+
+        rc = CIFSSMBOpen(xid, tcon, searchName, FILE_OPEN, GENERIC_READ,
+                         CREATE_NOT_DIR, &netfid, &oplock, &file_info,
+                         nls_codepage, remap);
+        if (rc != 0)
+                return rc;
+
+        if (file_info.EndOfFile != CIFS_MF_SYMLINK_FILE_SIZE) {
+                CIFSSMBClose(xid, tcon, netfid);
+                /* it's not a symlink */
+                return -EINVAL;
+        }
+
+        buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
+        if (!buf)
+                return -ENOMEM;
+        pbuf = buf;
+
+        rc = CIFSSMBRead(xid, tcon, netfid,
+                         CIFS_MF_SYMLINK_FILE_SIZE /* length */,
+                         0 /* offset */,
+                         &bytes_read, &pbuf, &buf_type);
+        CIFSSMBClose(xid, tcon, netfid);
+        if (rc != 0) {
+                kfree(buf);
+                return rc;
+        }
+
+        rc = CIFSParseMFSymlink(buf, bytes_read, &link_len, symlinkinfo);
+        kfree(buf);
+        if (rc != 0)
+                return rc;
+
+        return 0;
+}
+
 bool
 CIFSCouldBeMFSymlink(const struct cifs_fattr *fattr)
 {