ext4: prevent online resize with backup superblock

[cascardo/linux.git] / fs / cifs / connect.c

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 239e1fb..24fa08d 100644 (file)
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -70,6 +70,7 @@ enum {
        Opt_forcegid, Opt_noforcegid,
        Opt_noblocksend, Opt_noautotune,
        Opt_hard, Opt_soft, Opt_perm, Opt_noperm,
+       Opt_mapposix, Opt_nomapposix,
        Opt_mapchars, Opt_nomapchars, Opt_sfu,
        Opt_nosfu, Opt_nodfs, Opt_posixpaths,
        Opt_noposixpaths, Opt_nounix,
@@ -124,8 +125,10 @@ static const match_table_t cifs_mount_option_tokens = {
        { Opt_soft, "soft" },
        { Opt_perm, "perm" },
        { Opt_noperm, "noperm" },
-       { Opt_mapchars, "mapchars" },
+       { Opt_mapchars, "mapchars" }, /* SFU style */
        { Opt_nomapchars, "nomapchars" },
+       { Opt_mapposix, "mapposix" }, /* SFM style */
+       { Opt_nomapposix, "nomapposix" },
        { Opt_sfu, "sfu" },
        { Opt_nosfu, "nosfu" },
        { Opt_nodfs, "nodfs" },
@@ -1231,6 +1234,14 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
        vol->linux_uid = current_uid();
        vol->linux_gid = current_gid();
 
+       /*
+        * default to SFM style remapping of seven reserved characters
+        * unless user overrides it or we negotiate CIFS POSIX where
+        * it is unnecessary.  Can not simultaneously use more than one mapping
+        * since then readdir could list files that open could not open
+        */
+       vol->remap = true;
+
        /* default to only allowing write access to owner of the mount */
        vol->dir_mode = vol->file_mode = S_IRUGO | S_IXUGO | S_IWUSR;
 
@@ -1338,10 +1349,18 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
                        vol->noperm = 1;
                        break;
                case Opt_mapchars:
-                       vol->remap = 1;
+                       vol->sfu_remap = true;
+                       vol->remap = false; /* disable SFM mapping */
                        break;
                case Opt_nomapchars:
-                       vol->remap = 0;
+                       vol->sfu_remap = false;
+                       break;
+               case Opt_mapposix:
+                       vol->remap = true;
+                       vol->sfu_remap = false; /* disable SFU mapping */
+                       break;
+               case Opt_nomapposix:
+                       vol->remap = false;
                        break;
                case Opt_sfu:
                        vol->sfu_emul = 1;
@@ -3197,6 +3216,8 @@ void cifs_setup_cifs_sb(struct smb_vol *pvolume_info,
        if (pvolume_info->server_ino)
                cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_SERVER_INUM;
        if (pvolume_info->remap)
+               cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_MAP_SFM_CHR;
+       if (pvolume_info->sfu_remap)
                cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_MAP_SPECIAL_CHR;
        if (pvolume_info->no_xattr)
                cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NO_XATTR;
@@ -3239,10 +3260,20 @@ void cifs_setup_cifs_sb(struct smb_vol *pvolume_info,
        }
        if (pvolume_info->mfsymlinks) {
                if (pvolume_info->sfu_emul) {
-                       cifs_dbg(VFS, "mount option mfsymlinks ignored if sfu mount option is used\n");
-               } else {
-                       cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_MF_SYMLINKS;
+                       /*
+                        * Our SFU ("Services for Unix" emulation does not allow
+                        * creating symlinks but does allow reading existing SFU
+                        * symlinks (it does allow both creating and reading SFU
+                        * style mknod and FIFOs though). When "mfsymlinks" and
+                        * "sfu" are both enabled at the same time, it allows
+                        * reading both types of symlinks, but will only create
+                        * them with mfsymlinks format. This allows better
+                        * Apple compatibility (probably better for Samba too)
+                        * while still recognizing old Windows style symlinks.
+                        */
+                       cifs_dbg(VFS, "mount options mfsymlinks and sfu both enabled\n");
                }
+               cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_MF_SYMLINKS;
        }
 
        if ((pvolume_info->cifs_acl) && (pvolume_info->dynperm))
@@ -3330,8 +3361,7 @@ expand_dfs_referral(const unsigned int xid, struct cifs_ses *ses,
        ref_path = check_prefix ? full_path + 1 : volume_info->UNC + 1;
 
        rc = get_dfs_path(xid, ses, ref_path, cifs_sb->local_nls,
-                         &num_referrals, &referrals,
-                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
+                         &num_referrals, &referrals, cifs_remap(cifs_sb));
 
        if (!rc && num_referrals > 0) {
                char *fake_devname = NULL;