Re: [PATCH 12/13] xfs: add version 3 inode format with CRCs

Josef 'Jeff' Sipek
2009-02-12T06:39:13Z

On Tue, Feb 10, 2009 at 03:22:53PM -0500, Christoph Hellwig wrote:
...
> Index: xfs/fs/xfs/xfs_dinode.h
> ===================================================================
> --- xfs.orig/fs/xfs/xfs_dinode.h 2009-02-10 19:45:51.939069576 +0100
> +++ xfs/fs/xfs/xfs_dinode.h 2009-02-10 19:45:59.195068745 +0100
> @@ -69,11 +69,32 @@ typedef struct xfs_dinode {
>
> /* di_next_unlinked is the only non-core field in the old dinode */
> __be32 di_next_unlinked;/* agi unlinked list ptr */
> -} __attribute__((packed)) xfs_dinode_t;
> +
> + /* start of the extended dinode, writable fields */
> + __be32 di_crc; /* CRC of the inode */
> + __be64 di_changecount; /* number of attribute changes */
> + __u8 di_pad2[16]; /* more padding for future expansion */
> +
> + /* fields only written to during inode creation */
> + xfs_timestamp_t di_crtime; /* time created */
> + __be64 di_ino; /* inode number */
> + uuid_t di_uuid; /* UUID of the filesystem */
> +} xfs_dinode_t;

Hrm...removing the packed attribute... Eric, do you remember the ARM ABI
alignment rules? Regardless of ARM, are those fields aligned nicely? (From a
quick glance at the code looks ok.)

Also, why is the padding filed in the middle of these fields? IOW, why are
crtime/ino/uuid at the end?

Josef 'Jeff' Sipek.

--
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