cifs: Extract DFS referral expansion logic to separate function
The logic behind the expansion of DFS referrals is now extracted from
cifs_mount into a new static function, expand_dfs_referral. This will
reduce duplicate code in upcoming commits.
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Sean Finney <seanius@seanius.net>
Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Steve French <sfrench@us.ibm.com>
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 2b51199..b6c6a36 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -2745,6 +2745,57 @@
full_path[unc_len + cifs_sb->prepathlen] = 0; /* add trailing null */
return full_path;
}
+
+/*
+ * Perform a dfs referral query for a share and (optionally) prefix
+ *
+ * If a referral is found, mount_data will be set to point at a newly
+ * allocated string containing updated options for the submount.
+ * Otherwise it will be left untouched.
+ *
+ * Returns the rc from get_dfs_path to the caller, which can be used to
+ * determine whether there were referrals.
+ */
+static int
+expand_dfs_referral(int xid, struct cifsSesInfo *pSesInfo,
+ struct smb_vol *volume_info, struct cifs_sb_info *cifs_sb,
+ char **mount_data, int check_prefix)
+{
+ int rc;
+ unsigned int num_referrals = 0;
+ struct dfs_info3_param *referrals = NULL;
+ char *full_path = NULL, *ref_path = NULL, *mdata = NULL;
+
+ full_path = build_unc_path_to_root(volume_info, cifs_sb);
+ if (IS_ERR(full_path))
+ return PTR_ERR(full_path);
+
+ /* For DFS paths, skip the first '\' of the UNC */
+ ref_path = check_prefix ? full_path + 1 : volume_info->UNC + 1;
+
+ rc = get_dfs_path(xid, pSesInfo , ref_path, cifs_sb->local_nls,
+ &num_referrals, &referrals,
+ cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
+
+ if (!rc && num_referrals > 0) {
+ char *fake_devname = NULL;
+
+ mdata = cifs_compose_mount_options(cifs_sb->mountdata,
+ full_path + 1, referrals,
+ &fake_devname);
+
+ free_dfs_info_array(referrals, num_referrals);
+ kfree(fake_devname);
+
+ if (IS_ERR(mdata)) {
+ rc = PTR_ERR(mdata);
+ mdata = NULL;
+ }
+ *mount_data = mdata;
+ }
+ kfree(full_path);
+ return rc;
+}
#endif
int
@@ -2761,10 +2812,19 @@
char *mount_data = mount_data_global;
struct tcon_link *tlink;
#ifdef CONFIG_CIFS_DFS_UPCALL
- struct dfs_info3_param *referrals = NULL;
- unsigned int num_referrals = 0;
int referral_walks_count = 0;
try_mount_again:
+
+ /* cleanup activities if we're chasing a referral */
+ if (referral_walks_count) {
+ if (tcon)
+ cifs_put_tcon(tcon);
+ else if (pSesInfo)
+ cifs_put_smb_ses(pSesInfo);
+
+ cleanup_volume_info(&volume_info);
+ FreeXid(xid);
+ }
#endif
rc = 0;
tcon = NULL;
@@ -2910,46 +2970,19 @@
if ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS) == 0)
convert_delimiter(cifs_sb->prepath,
CIFS_DIR_SEP(cifs_sb));
- full_path = build_unc_path_to_root(volume_info, cifs_sb);
- if (IS_ERR(full_path)) {
- rc = PTR_ERR(full_path);
- goto mount_fail_check;
- }
- cFYI(1, "Getting referral for: %s", full_path);
- rc = get_dfs_path(xid, pSesInfo , full_path + 1,
- cifs_sb->local_nls, &num_referrals, &referrals,
- cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
- if (!rc && num_referrals > 0) {
- char *fake_devname = NULL;
+ if (mount_data != mount_data_global)
+ kfree(mount_data);
- if (mount_data != mount_data_global)
- kfree(mount_data);
+ rc = expand_dfs_referral(xid, pSesInfo, volume_info, cifs_sb,
+ &mount_data, true);
- mount_data = cifs_compose_mount_options(
- cifs_sb->mountdata, full_path + 1,
- referrals, &fake_devname);
-
- free_dfs_info_array(referrals, num_referrals);
- kfree(fake_devname);
- kfree(full_path);
-
- if (IS_ERR(mount_data)) {
- rc = PTR_ERR(mount_data);
- mount_data = NULL;
- goto mount_fail_check;
- }
-
- if (tcon)
- cifs_put_tcon(tcon);
- else if (pSesInfo)
- cifs_put_smb_ses(pSesInfo);
-
- cleanup_volume_info(&volume_info);
+ if (!rc) {
referral_walks_count++;
- FreeXid(xid);
goto try_mount_again;
}
+ mount_data = NULL;
+ goto mount_fail_check;
#else /* No DFS support, return error on mount */
rc = -EOPNOTSUPP;
#endif