Messages in this thread | | | Date | Tue, 1 Feb 2000 14:42:25 +0100 | From | Jens Axboe <> | Subject | Re: Block device request merging - repeated requests. |
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On Tue, Feb 01 2000, David Woodhouse wrote: > I see no CURRENT->b_rsector or b_blocknr. > > I assume you mean CURRENT->bh->{b_rsector,b_blocknr} ?
Yes, of course.
> Which? What's the difference? They are documented as "Real buffer location on > disk" and "block number" respectively, which doesn't really help me choose > between them.
I found that b_rsector is the 512 byte sector number and b_blocknr is relative to the block size of the device. b_blocknr is set with getblk() for example, and here you pass the actual location of the device. ll_rw_block() sets b_rsector to b_blocknr * (b_size >> 9), so there you have it.
-- * Jens Axboe <axboe@suse.de> * Linux CD-ROM Maintainer * http://www.kernel.dk
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