Re: [PATCH 03/10] xfs: consolidate mount option features in m_features

[Brian Foster <bfoster@redhat.com>]

On Mon, Aug 20, 2018 at 02:48:44PM +1000, Dave Chinner wrote:
> From: Dave Chinner <dchinner@redhat.com>
> 
> This provides separation of mount time feature flags from runtime
> mount flagsi and mount option state. It also makes the feature

s/flagsi/flags/

> checks use the same interface as the superblock features. i.e. we
> don't care if the feature is enabled by superblock flags or mount
> options, we just care if it's enabled or not.
> 
> Signed-off-by: Dave Chinner <dchinner@redhat.com>
> ---
>  fs/xfs/xfs_mount.h | 36 ++++++++++++++++++++++++++++++++++++
>  1 file changed, 36 insertions(+)
> 
> diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
> index 92d947f17c69..74a128fe316b 100644
> --- a/fs/xfs/xfs_mount.h
> +++ b/fs/xfs/xfs_mount.h
> @@ -225,6 +225,21 @@ typedef struct xfs_mount {
>  #define XFS_FEAT_META_UUID	(1ULL << 20)	/* metadata UUID */
>  #define XFS_FEAT_REALTIME	(1ULL << 21)	/* realtime device present */
>  
> +#define XFS_FEAT_WSYNC		(1ULL << 22)	/* synchronous metadata ops */
> +#define XFS_FEAT_DIRSYNC	(1ULL << 23)	/* synchronous directory ops */
> +#define XFS_FEAT_DISCARD	(1ULL << 24)	/* discard unused blocks */
> +#define XFS_FEAT_GRPID		(1ULL << 25)	/* group-ID assigned from directory */
> +#define XFS_FEAT_SMALL_INUMS	(1ULL << 26)	/* user wants 32bit inodes */
> +#define XFS_FEAT_IKEEP		(1ULL << 27)	/* keep empty inode clusters*/
> +#define XFS_FEAT_SWALLOC	(1ULL << 28)	/* stripe width allocation */
> +#define XFS_FEAT_FILESTREAMS	(1ULL << 29)	/* enable the filestreams
> +						   allocator */
> +#define XFS_FEAT_DAX		(1ULL << 30)	/* TEST ONLY! */
> +#define XFS_FEAT_COMPAT_IOSIZE	(1ULL << 31)	/* don't report large preferred
> +						 * I/O size in stat() */
> +#define XFS_FEAT_NORECOVERY	(1ULL << 32)	/* no recovery - dirty fs */
> +#define XFS_FEAT_NOUUID		(1ULL << 33)	/* ignore uuid during mount */

Similar indentation issue here..? Otherwise looks fine modulo the
previous comments on the broader API.

Brian

> +
>  #define __XFS_HAS_FEAT(name, NAME) \
>  static inline bool xfs_has_ ## name (struct xfs_mount *mp) \
>  { \
> @@ -250,6 +265,7 @@ static inline void xfs_feat_remove_ ## name (struct xfs_mount *mp) \
>  }
>  
>  
> +/* superblock features */
>  __XFS_HAS_ADDFEAT(attr, ATTR)
>  __XFS_HAS_FEAT(nlink, NLINK)
>  __XFS_HAS_ADDFEAT(quota, QUOTA)
> @@ -274,6 +290,26 @@ __XFS_HAS_FEAT(metauuid, META_UUID)
>  __XFS_HAS_FEAT(realtime, REALTIME)
>  
>  
> +/*
> + * Mount features
> + *
> + * These do not change dynamically - features that can come and go,
> + * such as 32 bit inodes and read-only state, are kept as flags rather than
> + * features.
> + */
> +__XFS_HAS_FEAT(wsync, WSYNC)
> +__XFS_HAS_FEAT(dirsync, DIRSYNC)
> +__XFS_HAS_FEAT(discard, DISCARD)
> +__XFS_HAS_FEAT(grpid, GRPID)
> +__XFS_HAS_FEAT(small_inums, SMALL_INUMS)
> +__XFS_HAS_FEAT(ikeep, IKEEP)
> +__XFS_HAS_FEAT(swalloc, SWALLOC)
> +__XFS_HAS_FEAT(filestreams, FILESTREAMS)
> +__XFS_HAS_FEAT(dax, DAX)
> +__XFS_HAS_FEAT(compat_iosize, COMPAT_IOSIZE)
> +__XFS_HAS_FEAT(norecovery, NORECOVERY)
> +__XFS_HAS_FEAT(nouuid, NOUUID)
> +
>  /*
>   * Flags for m_flags.
>   */
> -- 
> 2.17.0
>