Messages in this thread |  | | Date | Thu, 8 Mar 2001 10:51:41 +0100 | From | David Weinehall <> | Subject | Re: 64-bit capable block device layer |
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On Wed, Mar 07, 2001 at 07:53:23PM +0100, Jens Axboe wrote: > On Wed, Mar 07 2001, Rik van Riel wrote: > > > > how would you feel about having the block device layer 64-bit > > > > capable, so Linux can have block devices of more than 2GB in > > > > size ? > > > > > > I already did this here, or something similar at least. Using > > > a sector_t type that is 64-bit, regardless of platform. Is it > > > really worth it to differentiate and use 32-bit types for old > > > machines? > > > > Wonderful ! > > > > I'm not sure how expensive 64-bit arithmetic would be on > > eg. 386, 486 or 68k machines, or how much impact the extra > > memory taken would have. > > > > OTOH, I'm not sure what problems it could give to make this > > a compile-time option... > > Plus compile time options are nasty :-). It would probably make > bigger sense to completely skip all the merging etc for low end > machines. I think they already do this for embedded kernels (ie > removing ll_rw_blk.c and elevator.c). That avoids most of the > 64-bit arithmetic anyway.
My 386/486 and m68k-machines with 4/8/16 MB's of memory would be happy for any and all options to remove code only needed by larger machines. I'm pretty sure none of my 386:en will ever have 2GB of swap, 2GB of blockdevices or 2TB filesystems...
Of course, for embedded kernels, being able to exclude block-devices might be an idea. Or?
/David Weinehall _ _ // David Weinehall <tao@acc.umu.se> /> Northern lights wander \\ // Project MCA Linux hacker // Dance across the winter sky // \> http://www.acc.umu.se/~tao/ </ Full colour fire </ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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