XFS accessing arch-specific structures

[David Howells <dhowells@redhat.com>]

Hi Nathan,

I've got a problem in which XFS is accessing arch-specific structures, and
thus requiring those structures to conform to its ideals. Specifically, it's
trying to read the counter using atomic_read(), whether or not this is
possible:

    fs/xfs/linux-2.6/sema.h:
    #define valusema(sp)			(atomic_read(&(sp)->count))

    compile log:

      CC      fs/xfs/xfs_inode.o
      CC      fs/xfs/xfs_inode_item.o
    fs/xfs/xfs_inode_item.c: In function `xfs_inode_item_pushbuf':
    fs/xfs/xfs_inode_item.c:803: error: structure has no member named `count'
    fs/xfs/xfs_inode_item.c:825: error: structure has no member named `count'

Can you fix this please? This will not compile with all archs.

I'm told that Christoph Hellwig may have an idea or a patch that might provide
a fix. If it's necessary to get the count on the semaphore (which it might
be), then you should add a function to each asm/semaphore.h to retrieve it and
use that.

David