In message <[EMAIL PROTECTED]>, Brent Verner writes:
>On 04 Sep 2001 at 10:36 (+0200), Poul-Henning Kamp wrote:
>| Assignment:
>| The v_tag element in struct vnode is a debugging aid, but unfortunately
>| it is implemented in a way which means that adding a filesystem means
>| modifying the definition in <sys/vnode.h>.
>| Convert the v_tag to an "const char *" and have the filesystems put
>| their name in there instead.
>| The v_tag has been abused a few places, easily recognizable by the fact
>| that the kernel should never inspect the value of v_tag.
>| These places should be easily changeable to use the new representation.
>| Please mark them with a big fat "/*XXX: ABUSE OF v_tag */" comment.
>#include <newbie_kernel_hacker_warning.h>
>I've done a /cursory/ look over how this v_tag is used.  I'm not sure
>this is a simple/clean as you propose, since this is used in the 
>IS_LOCKING_VFS macro, as well as in union_subr.c...

Well, that is just too bad, because IS_LOCKING_VFS is wrong then.

The places which inspect v_tag will have to be changed to use
strcmp() then...

Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
[EMAIL PROTECTED]         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.

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