Hello,
Please let me know if there are any suggestions or reviews on this patch.
Thank you in advance,
Ojaswin
On Mon, Apr 18, 2022 at 02:05:45PM +0530, Ojaswin Mujoo wrote:
> In __ext4_super() we always overwrote the user specified journal_ioprio
> value with a default value, expecting parse_apply_sb_mount_options() to
> later correctly set ctx->journal_ioprio to the user specified value.
> However, if parse_apply_sb_mount_options() returned early because of
> empty sbi->es_s->s_mount_opts, the correct journal_ioprio value was
> never set.
>
> This patch fixes __ext4_super() to only use the default value if the
> user has not specified any value for journal_ioprio.
>
> Similarly, the remount behavior was to either use journal_ioprio
> value specified during initial mount, or use the default value
> irrespective of the journal_ioprio value specified during remount.
> This patch modifies this to first check if a new value for ioprio
> has been passed during remount and apply it. Incase, no new value is
> passed, use the value specified during initial mount.
>
> Signed-off-by: Ojaswin Mujoo <ojaswin@xxxxxxxxxxxxx>
> ---
> fs/ext4/super.c | 15 ++++++++++-----
> 1 file changed, 10 insertions(+), 5 deletions(-)
>
> diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> index c5a9ffbf7f4f..bfd767c51203 100644
> --- a/fs/ext4/super.c
> +++ b/fs/ext4/super.c
> @@ -4427,7 +4427,8 @@ static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)
> int silent = fc->sb_flags & SB_SILENT;
>
> /* Set defaults for the variables that will be set during parsing */
> - ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
> + if (!(ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO))
> + ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
>
> sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
> sbi->s_sectors_written_start =
> @@ -6289,7 +6290,6 @@ static int __ext4_remount(struct fs_context *fc, struct super_block *sb)
> char *to_free[EXT4_MAXQUOTAS];
> #endif
>
> - ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
>
> /* Store the original options */
> old_sb_flags = sb->s_flags;
> @@ -6315,9 +6315,14 @@ static int __ext4_remount(struct fs_context *fc, struct super_block *sb)
> } else
> old_opts.s_qf_names[i] = NULL;
> #endif
> - if (sbi->s_journal && sbi->s_journal->j_task->io_context)
> - ctx->journal_ioprio =
> - sbi->s_journal->j_task->io_context->ioprio;
> + if (!(ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO)) {
> + if (sbi->s_journal && sbi->s_journal->j_task->io_context)
> + ctx->journal_ioprio =
> + sbi->s_journal->j_task->io_context->ioprio;
> + else
> + ctx->journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
> +
> + }
>
> ext4_apply_options(fc, sb);
>
> --
> 2.27.0
>
