Hi Steve,
We should still talk about kiobufs I guess....
There are some defines you could use as a trigger, for instance in
linux/fs.h there is
#define IS_KIOBUFIO(inode) __IS_FLG(inode, MS_KIOBUFIO)
so an
#ifdef IS_KIOBUFIO
would do it.
Not pretty, but it would work.
Steve
> On Wed, 7 Mar 2001, Chaitanya Tumuluri wrote:
> >> On Wed, 7 Mar 2001, Peter T. Breuer wrote:
> >> "GCS wrote:"
> >> I would appreciate it if the patch were less invasive. Has this been
> >> done? Surely changing make_request's type is intrinsically a bad idea?
> >>
> >> I agree that the implementation is clever - setting the bh argument null
> >> signals the new make_request to use the remaining args, kiobuff and
> >> friends, instead, so only kiobuff-aware code will make use of it. But
> >> in that case why not write a separate function? The kernel has
> >> provisions for overwriting make_request _cleanly_.
>
> > Agreed. The current state of the code is a historical artifact of trying
> > to keep pace with the evolutions in ll_rw_block/__make_request() and
> > friends. Originally, we did have a separate make_kio_request() function.
> > The provision you mention came in later, at which point in time it was
> going
> > to be a _lot_ more effort to provide for lvm/md type of remapping in the
> > make_kio_request() version. A quicker/easier fix was to modify the
> > make_request() signature to handle kiobufs.
>
> Is there any way to determine if the kiobufs support is in the kernel at
> compile time? Community members would like to build JFS on the SGI kernel
> and in our code we use
> generic_make_request(READ, &bp->l_bh); /* 2.4.x kernel */
>
> This call would change to
> generic_make_request(READ, &bp->l_bh, NULL, 0, 0, 0); /* kiobufs support */
>
> I would like to find a clean way to ifdef this. Anyone have any ideas
> with this one.
>
> Thanks,
> Steve
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