CIFS: Add SMB2 support for hardlink operation

Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>

6 files changed, 76 insertions, 6 deletions

diff --git a/fs/cifs/smb2glob.h b/fs/cifs/smb2glob.h
index 8635574ea8b6..21555d8744fd 100644
--- a/fs/cifs/smb2glob.h
+++ b/fs/cifs/smb2glob.h
@@ -40,6 +40,7 @@
 #define SMB2_OP_MKDIR 5
 #define SMB2_OP_RENAME 6
 #define SMB2_OP_DELETE 7
+#define SMB2_OP_HARDLINK 8
 
 /* Used when constructing chained read requests. */
 #define CHAINED_REQUEST 1
diff --git a/fs/cifs/smb2inode.c b/fs/cifs/smb2inode.c
index a6952bafe331..1921c9c87ccd 100644
--- a/fs/cifs/smb2inode.c
+++ b/fs/cifs/smb2inode.c
@@ -78,6 +78,10 @@ smb2_open_op_close(const unsigned int xid, struct cifs_tcon *tcon,
                 tmprc = SMB2_rename(xid, tcon, persistent_fid, volatile_fid,
                                     (__le16 *)data);
                 break;
+        case SMB2_OP_HARDLINK:
+                tmprc = SMB2_set_hardlink(xid, tcon, persistent_fid,
+                                          volatile_fid, (__le16 *)data);
+                break;
         default:
                 cERROR(1, "Invalid command");
                 break;
@@ -175,10 +179,10 @@ smb2_unlink(const unsigned int xid, struct cifs_tcon *tcon, const char *name,
                                   SMB2_OP_DELETE);
 }
 
-int
-smb2_rename_path(const unsigned int xid, struct cifs_tcon *tcon,
-                 const char *from_name, const char *to_name,
-                 struct cifs_sb_info *cifs_sb)
+static int
+smb2_set_path_attr(const unsigned int xid, struct cifs_tcon *tcon,
+                   const char *from_name, const char *to_name,
+                   struct cifs_sb_info *cifs_sb, __u32 access, int command)
 {
         __le16 *smb2_to_name = NULL;
         int rc;
@@ -189,9 +193,27 @@ smb2_rename_path(const unsigned int xid, struct cifs_tcon *tcon,
                 goto smb2_rename_path;
         }
 
-        rc = smb2_open_op_close(xid, tcon, cifs_sb, from_name, DELETE,
-                                FILE_OPEN, 0, 0, smb2_to_name, SMB2_OP_RENAME);
+        rc = smb2_open_op_close(xid, tcon, cifs_sb, from_name, access,
+                                FILE_OPEN, 0, 0, smb2_to_name, command);
 smb2_rename_path:
         kfree(smb2_to_name);
         return rc;
 }
+
+int
+smb2_rename_path(const unsigned int xid, struct cifs_tcon *tcon,
+                 const char *from_name, const char *to_name,
+                 struct cifs_sb_info *cifs_sb)
+{
+        return smb2_set_path_attr(xid, tcon, from_name, to_name, cifs_sb,
+                                  DELETE, SMB2_OP_RENAME);
+}
+
+int
+smb2_create_hardlink(const unsigned int xid, struct cifs_tcon *tcon,
+                     const char *from_name, const char *to_name,
+                     struct cifs_sb_info *cifs_sb)
+{
+        return smb2_set_path_attr(xid, tcon, from_name, to_name, cifs_sb,
+                                  FILE_READ_ATTRIBUTES, SMB2_OP_HARDLINK);
+}
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index 5aaccb0f3aae..75693e983e76 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -452,6 +452,7 @@ struct smb_version_operations smb21_operations = {
         .rmdir = smb2_rmdir,
         .unlink = smb2_unlink,
         .rename = smb2_rename_path,
+        .create_hardlink = smb2_create_hardlink,
         .open = smb2_open_file,
         .set_fid = smb2_set_fid,
         .close = smb2_close_file,
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 1dc11ce7934e..a684c4ab42d6 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -1709,3 +1709,34 @@ SMB2_rename(const unsigned int xid, struct cifs_tcon *tcon,
         kfree(data);
         return rc;
 }
+
+int
+SMB2_set_hardlink(const unsigned int xid, struct cifs_tcon *tcon,
+                  u64 persistent_fid, u64 volatile_fid, __le16 *target_file)
+{
+        struct smb2_file_link_info info;
+        void **data;
+        unsigned int size[2];
+        int rc;
+        int len = (2 * UniStrnlen((wchar_t *)target_file, PATH_MAX));
+
+        data = kmalloc(sizeof(void *) * 2, GFP_KERNEL);
+        if (!data)
+                return -ENOMEM;
+
+        info.ReplaceIfExists = 0; /* 1 = replace existing link with new */
+                              /* 0 = fail if link already exists */
+        info.RootDirectory = 0;  /* MBZ for network ops (why does spec say?) */
+        info.FileNameLength = cpu_to_le32(len);
+
+        data[0] = &info;
+        size[0] = sizeof(struct smb2_file_link_info);
+
+        data[1] = target_file;
+        size[1] = len + 2 /* null */;
+
+        rc = send_set_info(xid, tcon, persistent_fid, volatile_fid,
+                           FILE_LINK_INFORMATION, 2, data, size);
+        kfree(data);
+        return rc;
+}
diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h
index b03ca37d0d58..0f3c4828cd00 100644
--- a/fs/cifs/smb2pdu.h
+++ b/fs/cifs/smb2pdu.h
@@ -653,6 +653,15 @@ struct smb2_file_rename_info { /* encoding of request for level 10 */
         char   FileName[0];     /* New name to be assigned */
 } __packed; /* level 10 Set */
 
+struct smb2_file_link_info { /* encoding of request for level 11 */
+        __u8   ReplaceIfExists; /* 1 = replace existing link with new */
+                                /* 0 = fail if link already exists */
+        __u8   Reserved[7];
+        __u64  RootDirectory;  /* MBZ for network operations (why says spec?) */
+        __le32 FileNameLength;
+        char   FileName[0];     /* Name to be assigned to new link */
+} __packed; /* level 11 Set */
+
 /*
  * This level 18, although with struct with same name is different from cifs
  * level 0x107. Level 0x107 has an extra u64 between AccessFlags and
diff --git a/fs/cifs/smb2proto.h b/fs/cifs/smb2proto.h
index b43036e8ad2a..99f6945c8643 100644
--- a/fs/cifs/smb2proto.h
+++ b/fs/cifs/smb2proto.h
@@ -68,6 +68,9 @@ extern int smb2_unlink(const unsigned int xid, struct cifs_tcon *tcon,
 extern int smb2_rename_path(const unsigned int xid, struct cifs_tcon *tcon,
                             const char *from_name, const char *to_name,
                             struct cifs_sb_info *cifs_sb);
+extern int smb2_create_hardlink(const unsigned int xid, struct cifs_tcon *tcon,
+                                const char *from_name, const char *to_name,
+                                struct cifs_sb_info *cifs_sb);
 
 extern int smb2_open_file(const unsigned int xid, struct cifs_tcon *tcon,
                           const char *full_path, int disposition,
@@ -112,5 +115,8 @@ extern int SMB2_echo(struct TCP_Server_Info *server);
 extern int SMB2_rename(const unsigned int xid, struct cifs_tcon *tcon,
                        u64 persistent_fid, u64 volatile_fid,
                        __le16 *target_file);
+extern int SMB2_set_hardlink(const unsigned int xid, struct cifs_tcon *tcon,
+                             u64 persistent_fid, u64 volatile_fid,
+                             __le16 *target_file);
 
 #endif                  /* _SMB2PROTO_H */