cvs commit: src/sys/conf NOTES files options src/sys/kern vfs_bio.c src/sys/ufs/ffs ffs_rawread.c ffs_vnops.c

[Poul-Henning Kamp]

In message <200303262340.h2QNegJg065498 at repoman.freebsd.org>, Tor Egge writes:
>tegge       2003/03/26 15:40:42 PST
>
>  FreeBSD src repository
>
>  Modified files:
>    sys/conf             NOTES files options 
>    sys/kern             vfs_bio.c 
>    sys/ufs/ffs          ffs_vnops.c 
>  Added files:
>    sys/ufs/ffs          ffs_rawread.c 
>  Log:
>  Add support for reading directly from file to userland buffer when the
>  O_DIRECT descriptor status flag is set and both offset and length is a
>  multiple of the physical media sector size.

I am neither impressed nor thrilled by this.

We already have pretty firm plans for converting struct bio from a
"mapped KVM" to a a "virtual/physical scatter/gather" thing in the
6-current, and that is the correct way to solve this problem.

If this is a crucial feature for 5-stable, I would far rather add
we push ahead with that plan, than see more pbuf based hacks in the
kernel.

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