Re: [PATCH v3 1/1] bcachefs: Move BCACHEFS_STATFS_MAGIC value to UAPI magic.h

[Brian Foster]

On Tue, May 07, 2024 at 05:37:57PM +0200, Petr Vorel wrote:
> Move BCACHEFS_STATFS_MAGIC value to UAPI <linux/magic.h> under
> BCACHEFS_SUPER_MAGIC definition (use common approach for name) and reuse the
> definition in bcachefs_format.h BCACHEFS_STATFS_MAGIC.
> 
> There are other bcachefs magic definitions: BCACHE_MAGIC, BCHFS_MAGIC,
> which use UUID_INIT() and are used only in libbcachefs. Therefore move
> only BCACHEFS_STATFS_MAGIC value, which can be used outside of
> libbcachefs for f_type field in struct statfs in statfs() or fstatfs().
> 
> Suggested-by: Su Yue <l@xxxxxxxxxxx>
> Signed-off-by: Petr Vorel <pvorel@xxxxxxx>
> ---

I was thinking you'd just rename the STATFS_MAGIC def locally as well,
but whatever.. LGTM, thanks for the tweaks!

Acked-by: Brian Foster <bfoster@xxxxxxxxxx>

> Changes v2->v3:
> * Align tab with other entries.
> 
> Changes v1->v2 (all suggested by Brian Foster - thanks!):
> * rename constant to BCACHEFS_SUPER_MAGIC,
> * keep BCACHEFS_STATFS_MAGIC in bcachefs_format.h, just include
>  <uapi/linux/magic.h> and use BCACHEFS_SUPER_MAGIC definition,
> * move the constant to the first chunk.
> 
> Kind regards,
> Petr
> 
>  fs/bcachefs/bcachefs_format.h | 3 ++-
>  include/uapi/linux/magic.h    | 1 +
>  2 files changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/bcachefs/bcachefs_format.h b/fs/bcachefs/bcachefs_format.h
> index f7fbfccd2b1e..3b831415409b 100644
> --- a/fs/bcachefs/bcachefs_format.h
> +++ b/fs/bcachefs/bcachefs_format.h
> @@ -76,6 +76,7 @@
>  #include <asm/byteorder.h>
>  #include <linux/kernel.h>
>  #include <linux/uuid.h>
> +#include <uapi/linux/magic.h>
>  #include "vstructs.h"
>  
>  #ifdef __KERNEL__
> @@ -1275,7 +1276,7 @@ enum bch_compression_opts {
>  	UUID_INIT(0xc68573f6, 0x66ce, 0x90a9,				\
>  		  0xd9, 0x6a, 0x60, 0xcf, 0x80, 0x3d, 0xf7, 0xef)
>  
> -#define BCACHEFS_STATFS_MAGIC		0xca451a4e
> +#define BCACHEFS_STATFS_MAGIC		BCACHEFS_SUPER_MAGIC
>  
>  #define JSET_MAGIC		__cpu_to_le64(0x245235c1a3625032ULL)
>  #define BSET_MAGIC		__cpu_to_le64(0x90135c78b99e07f5ULL)
> diff --git a/include/uapi/linux/magic.h b/include/uapi/linux/magic.h
> index 1b40a968ba91..bb575f3ab45e 100644
> --- a/include/uapi/linux/magic.h
> +++ b/include/uapi/linux/magic.h
> @@ -37,6 +37,7 @@
>  #define HOSTFS_SUPER_MAGIC	0x00c0ffee
>  #define OVERLAYFS_SUPER_MAGIC	0x794c7630
>  #define FUSE_SUPER_MAGIC	0x65735546
> +#define BCACHEFS_SUPER_MAGIC	0xca451a4e
>  
>  #define MINIX_SUPER_MAGIC	0x137F		/* minix v1 fs, 14 char names */
>  #define MINIX_SUPER_MAGIC2	0x138F		/* minix v1 fs, 30 char names */
> -- 
> 2.43.0
>