tune2fs: Remove support for clearing the SPARSE_SUPER feature

Clearing SPARSE_SUPER is dangerous; it can result in a filesystem
which e2fsck can't fix easily.  Since there is very few good reasons
for wanting to turn this feature off, disable tune2fs's abiity to do
this.  Users who really want this can use debugfs.

Also, deprecate the tune2fs -s option.  Remove it from the man page
and usage message.

Addresses-Sourceforge-Bug: #1840286

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

diff --git a/misc/tune2fs.8.in b/misc/tune2fs.8.in
index ff8ae48..8b59c17 100644 (file)
--- a/misc/tune2fs.8.in
+++ b/misc/tune2fs.8.in
@@ -461,12 +461,6 @@ can be run to convert existing directories to the hashed B-tree format.
 .BI \-r " reserved-blocks-count"
 Set the number of reserved filesystem blocks.
 .TP
-.BR \-s " [" 0 | 1 ]
-Turn the sparse super feature off or on.  Turning this feature on
-saves space on really big filesystems.  This is the same as using the
-.B "\-O sparse_super"
-option.
-.TP
 .BI \-T " time-last-checked"
 Set the time the filesystem was last checked using
 .BR  e2fsck .

diff --git a/misc/tune2fs.c b/misc/tune2fs.c
index 184b5d6..4f66d42 100644 (file)
--- a/misc/tune2fs.c
+++ b/misc/tune2fs.c
@@ -97,10 +97,11 @@ static void usage(void)
        fprintf(stderr,
                _("Usage: %s [-c max_mounts_count] [-e errors_behavior] "
                  "[-g group]\n"
-                 "\t[-i interval[d|m|w]] [-j] [-J journal_options]\n"
-                 "\t[-l] [-s sparse_flag] [-m reserved_blocks_percent]\n"
-                 "\t[-o [^]mount_options[,...]] [-r reserved_blocks_count]\n"
-                 "\t[-u user] [-C mount_count] [-L volume_label]\n"
+                 "\t[-i interval[d|m|w]] [-j] [-J journal_options] [-l]\n"
+                 "\t[-m reserved_blocks_percent] "
+                 "[-o [^]mount_options[,...]] \n"
+                 "\t[-r reserved_blocks_count] [-u user] [-C mount_count] "
+                 "[-L volume_label]\n"
                  "\t[-M last_mounted_dir] [-O [^]feature[,...]]\n"
                  "\t[-E extended-option[,...]] [-T last_check_time] "
                  "[-U UUID] device\n"), program_name);
@@ -126,8 +127,7 @@ static __u32 clear_ok_features[3] = {
        /* Incompat */
        EXT2_FEATURE_INCOMPAT_FILETYPE,
        /* R/O compat */
-       EXT2_FEATURE_RO_COMPAT_LARGE_FILE |
-               EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER
+       EXT2_FEATURE_RO_COMPAT_LARGE_FILE
 };
 
 /*
@@ -719,7 +719,7 @@ static void parse_tune2fs_options(int argc, char **argv)
                                r_flag = 1;
                                open_flag = EXT2_FLAG_RW;
                                break;
-                       case 's':
+                       case 's': /* Deprecated */
                                s_flag = atoi(optarg);
                                open_flag = EXT2_FLAG_RW;
                                break;
@@ -1005,19 +1005,9 @@ int main (int argc, char ** argv)
                }
        }
        if (s_flag == 0) {
-               if (!(sb->s_feature_ro_compat &
-                     EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER))
-                       fputs(_("\nThe filesystem already has sparse "
-                               "superblocks disabled.\n"), stderr);
-               else {
-                       sb->s_feature_ro_compat &=
-                               ~EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER;
-                       sb->s_state &= ~EXT2_VALID_FS;
-                       fs->flags |= EXT2_FLAG_MASTER_SB_ONLY;
-                       ext2fs_mark_super_dirty(fs);
-                       printf(_("\nSparse superblock flag cleared.  %s"),
-                              _(please_fsck));
-               }
+               fputs(_("\nClearing the sparse superflag not supported.\n"),
+                     stderr);
+               exit(1);
        }
        if (T_flag) {
                sb->s_lastcheck = last_check_time;