Re: [PATCH VER 6] Extend project quotas to support 32bit project identifiers.

Alex Elder
2010-10-01T13:56:59Z

On Sun, 2010-09-26 at 08:10 +0200, Arkadiusz Miśkiewicz wrote:
> This patch adds support for 32bit project quota identifiers.
>
> On disk format is backward compatible with 16bit projid numbers. projid
> on disk is now keept in two 16bit values - di_projid_lo (which holds the
> same position as old 16bit projid value) and new di_projid_hi (takes
> existing padding) and convertes from/to 32bit value on the fly.
>
> xfs_admin (for existing fs), mkfs.xfs (for new fs) needs to be used
> to enable PROJID32BIT support.
>
> Signed-off-by: Arkadiusz Miśkiewicz <arekm@maven.pl>
> Reviewed-by: Christoph Hellwig <hch@lst.de>
> ---

Minor suggestion, below (which I can implement), otherwise this
looks good.

I didn't review it as carefully this time. But the model now
is that 32-bit project id's are only supported if the filesystem
has that feature bit set. And the feature bit is only set at
mkfs time or by xfs_db (not automatically as you had it before).
This sounds good to me.

Reviewed-by: Alex Elder <aelder@sgi.com>

> News:
> - use 0x80 instead of 0x20 for PROJID32BIT superblock bit (as 0x20
> and 0x40 are reserved)
> - style fix

. . .

> diff --git a/fs/xfs/linux-2.6/xfs_ioctl32.h b/fs/xfs/linux-2.6/xfs_ioctl32.h
> index 1024c4f..f92d662 100644
> --- a/fs/xfs/linux-2.6/xfs_ioctl32.h
> +++ b/fs/xfs/linux-2.6/xfs_ioctl32.h
> @@ -65,8 +65,9 @@ typedef struct compat_xfs_bstat {
> __s32 bs_extsize; /* extent size */
> __s32 bs_extents; /* number of extents */
> __u32 bs_gen; /* generation count */
> - __u16 bs_projid; /* project id */
> - unsigned char bs_pad[14]; /* pad space, unused */
> + __u16 bs_projid; /* lower part of project id */

This could be:
__u16 bs_projid_lo; /* ... */
#define bs_projid bs_projid_lo

...to make it work with old code but be more consistent with new.

> + __u16 bs_projid_hi; /* high part of project id */
> + unsigned char bs_pad[12]; /* pad space, unused */
> __u32 bs_dmevmask; /* DMIG event mask */
> __u16 bs_dmstate; /* DMIG state info */
> __u16 bs_aextents; /* attribute number of extents */

. . .

> diff --git a/fs/xfs/xfs_fs.h b/fs/xfs/xfs_fs.h
> index 87c2e9d..ae1c500 100644
> --- a/fs/xfs/xfs_fs.h
> +++ b/fs/xfs/xfs_fs.h
> @@ -293,9 +293,10 @@ typedef struct xfs_bstat {
> __s32 bs_extsize; /* extent size */
> __s32 bs_extents; /* number of extents */
> __u32 bs_gen; /* generation count */
> - __u16 bs_projid; /* project id */
> + __u16 bs_projid; /* lower part of project id */

Same thing here.

> __u16 bs_forkoff; /* inode fork offset in bytes */
> - unsigned char bs_pad[12]; /* pad space, unused */
> + __u16 bs_projid_hi; /* higher part of project id */
> + unsigned char bs_pad[10]; /* pad space, unused */
> __u32 bs_dmevmask; /* DMIG event mask */
> __u16 bs_dmstate; /* DMIG state info */
> __u16 bs_aextents; /* attribute number of extents */

. . .