Previously, /proc/fs/ext4/<dev>/options would only show binary options if they were set (1 in the options bit mask). E.g. it would show "grpid" if it was set, but it would not show "nogrpid" if grpid was not set. This seems sensible, but when an option is absent from the file, it can be hard for the unfamiliar to know what is being used. E.g. if there isn't a (no)grpid entry, nogrpid is in effect. But if there isn't a (no)auto_da_alloc entry, auto_da_alloc is in effect. If there isn't a (minixdf|bsddf) entry, it turns out bsddf is in effect. It all depends on how the option is implemented. It's clearer to be explicit, so print the corresponding option regardless of whether it means a 1 or a 0 in the bit mask. Note that options which do not have an explicit disable option aren't indicated as being disabled even with this change (e.g. dax). Signed-off-by: Tyson Nottingham <tgnottingham@xxxxxxxxx> --- Before: $ cat /proc/fs/ext4/loop0/options rw block_validity delalloc journal_checksum barrier user_xattr acl resuid=0 resgid=0 errors=continue commit=5 min_batch_time=0 max_batch_time=15000 stripe=0 data=ordered inode_readahead_blks=32 init_itable=10 max_dir_size_kb=0 After (additions starred): $ cat /proc/fs/ext4/loop0/options rw *bsddf *nogrpid block_validity *dioread_lock *nodiscard delalloc journal_checksum barrier *auto_da_alloc user_xattr acl *noquota resuid=0 resgid=0 errors=continue commit=5 min_batch_time=0 max_batch_time=15000 stripe=0 data=ordered inode_readahead_blks=32 init_itable=10 max_dir_size_kb=0 --- fs/ext4/super.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/fs/ext4/super.c b/fs/ext4/super.c index e82e35a..6b07fa2 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -2018,7 +2018,7 @@ static int _ext4_show_options(struct seq_file *seq, struct super_block *sb, { struct ext4_sb_info *sbi = EXT4_SB(sb); struct ext4_super_block *es = sbi->s_es; - int def_errors, def_mount_opt = nodefs ? 0 : sbi->s_def_mount_opt; + int def_errors, def_mount_opt = sbi->s_def_mount_opt; const struct mount_opts *m; char sep = nodefs ? '\n' : ','; @@ -2033,7 +2033,7 @@ static int _ext4_show_options(struct seq_file *seq, struct super_block *sb, if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) || (m->flags & MOPT_CLEAR_ERR)) continue; - if (!(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt))) + if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt))) continue; /* skip if same as the default */ if ((want_set && (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) || @@ -2067,7 +2067,8 @@ static int _ext4_show_options(struct seq_file *seq, struct super_block *sb, SEQ_OPTS_PUTS("i_version"); if (nodefs || sbi->s_stripe) SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe); - if (EXT4_MOUNT_DATA_FLAGS & (sbi->s_mount_opt ^ def_mount_opt)) { + if (nodefs || EXT4_MOUNT_DATA_FLAGS & + (sbi->s_mount_opt ^ def_mount_opt)) { if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) SEQ_OPTS_PUTS("data=journal"); else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) -- 2.7.4