On Wed, Dec 22, 2021 at 09:06:22AM +0800, yebin wrote:
>
>
> On 2021/12/21 22:43, Lukas Czerner wrote:
> > Hi,
> >
> > nice catch. This is a bug indeed. However I am currently in a process of
> > changing the ctx_set/clear/test_ helpers because currently it generates
> > functions that are unused.
> >
> > While I am at it I can just create a custom ctx_set_mount_flags()
> > helper that would behave as expected so that we won't have to specify
> > "1 < EXT4_MF_FS_ABORTED" which is not really obvious and hence error
> > prone.
> Actually, I fixed the first version as follows:
Allright, this looks better.
>
> diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> index b72d989b77fb..199920ffc7d3 100644
> --- a/fs/ext4/super.c
> +++ b/fs/ext4/super.c
> @@ -2049,8 +2049,8 @@ struct ext4_fs_context {
> unsigned int mask_s_mount_opt;
> unsigned int vals_s_mount_opt2;
> unsigned int mask_s_mount_opt2;
> - unsigned int vals_s_mount_flags;
> - unsigned int mask_s_mount_flags;
> + unsigned long vals_s_mount_flags;
> + unsigned long mask_s_mount_flags;
> unsigned int opt_flags; /* MOPT flags */
> unsigned int spec;
> u32 s_max_batch_time;
> @@ -2166,7 +2166,12 @@ static inline bool ctx_test_##name(struct ext4_fs_context *ctx, int flag)\
> EXT4_SET_CTX(flags);
> EXT4_SET_CTX(mount_opt);
> EXT4_SET_CTX(mount_opt2);
> -EXT4_SET_CTX(mount_flags);
> +
> +static inline void ctx_set_mount_flags(struct ext4_fs_context *ctx, int bit)
Maybe ctx_set_mount_flag since you can't really set more than one this
way?
> +{
> + set_bit(bit, &ctx->mask_s_mount_flags);
> + set_bit(bit, &ctx->vals_s_mount_flags);
> +}
>
>
> I think 'mask_s_mount_flags' is useless now.
So how would we know what flags have changed ? Sure, there is currently
no need to clear the flag but that can come in future and once it does
we'll only need to create a clear helper, the rest will be ready.
I'd rather keep it.
-Lukas
> >
> > My plan is to send my patch set including this one tomorrow, will that
> > be fine with you ?
> >
> > -Lukas
> >
> > On Tue, Dec 21, 2021 at 08:32:14PM +0800, Ye Bin wrote:
> > > We test remount with 'abort' option as follows:
> > > [root@localhost home]# mount /dev/sda test
> > > [root@localhost home]# mount | grep test
> > > /dev/sda on /home/test type ext4 (rw,relatime)
> > > [root@localhost home]# mount -o remount,abort test
> > > [root@localhost home]# mount | grep test
> > > /dev/sda on /home/test type ext4 (rw,relatime)
> > >
> > > Obviously, remount 'abort' option isn't effective.
> > > After 6e47a3cc68fc commit we process abort option with 'ctx_set_mount_flags':
> > > static inline void ctx_set_mount_flags(struct ext4_fs_context *ctx, int flag)
> > > {
> > > ctx->mask_s_mount_flags |= flag;
> > > ctx->vals_s_mount_flags |= flag;
> > > }
> > >
> > > But we test 'abort' option with 'ext4_test_mount_flag':
> > > static inline int ext4_test_mount_flag(struct super_block *sb, int bit)
> > > {
> > > return test_bit(bit, &EXT4_SB(sb)->s_mount_flags);
> > > }
> > >
> > > To solve this issue, pass (1 << EXT4_MF_FS_ABORTED) to 'ctx_set_mount_flags'.
> > >
> > > Fixes:6e47a3cc68fc("ext4: get rid of super block and sbi from handle_mount_ops()")
> > > Signed-off-by: Ye Bin <yebin10@xxxxxxxxxx>
> > > ---
> > > fs/ext4/super.c | 2 +-
> > > 1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> > > index b72d989b77fb..071b7b3c5678 100644
> > > --- a/fs/ext4/super.c
> > > +++ b/fs/ext4/super.c
> > > @@ -2236,7 +2236,7 @@ static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param)
> > > param->key);
> > > return 0;
> > > case Opt_abort:
> > > - ctx_set_mount_flags(ctx, EXT4_MF_FS_ABORTED);
> > > + ctx_set_mount_flags(ctx, 1 << EXT4_MF_FS_ABORTED);
> > > return 0;
> > > case Opt_i_version:
> > > ctx_set_flags(ctx, SB_I_VERSION);
> > > --
> > > 2.31.1
> > >
> > .
> >
>
