On 7/25/13 1:43 PM, Dwight Engen wrote: > On Thu, 25 Jul 2013 10:23:19 -0500 > Eric Sandeen <sandeen@xxxxxxxxxxx> wrote: > > [...] >> (You can probably mkfs w/ an explicit 512 sector size, and confirm >> that 512-byte DIOs work again) > > Hi Eric, yep, confirmed that doing mkfs.xfs -b size=1024 (used 1024 > instead of 512 so that 240 would run) makes 091, 240, and 268 work > without my changes. Ok; that's because a specified block size < physical sector size switches the "sector size" setting in the superblock back down to logical sector size. -b 4096 -s 512 should make it work too. >> bleah, perhaps that was a mistake - or perhaps we need to fix >> kernelspace to prefer physical-size IOs, but allow logical-size if a >> DIO requests it. > > ext4 and btrfs did work, so perhaps that is what they are doing, I > have not looked yet. well, they probably don't have this "sector size" notion throughout the code like we do. > [... test 240] >>>>>> -logical_block_size=`blockdev --getss $TEST_DEV` >>>>>> +logical_block_size=`blockdev --getpbsz $TEST_DEV` >>>>> >>>>> FWIW, that doesn't make much sense - putting the physical block >>>>> size into a variable named "logical_block_size"..... >>> >>> Yeah, that name wouldn't make much sense with this change. Its >>> actually being used to compare to the fs block size and then its >>> passed into aiodio_sparse2 as offset. 091 and 268 use the more >>> generic name bsize, should I can change it to that? >> >> Well, that was put there with: >> >> commit 2dbd21dc152d89715263990c881025f17c7b632e >> Author: Jeff Moyer <jmoyer@xxxxxxxxxx> >> Date: Fri Feb 11 15:20:02 2011 -0500 >> >> 240: only run when the file system block size is larger than the >> disk sector size >> This test really wants to test partial file-system block I/Os. >> Thus, if the device has a 4K sector size, and the file system has a >> 4K block size, there's really no point in running the test. In the >> attached patch, I check that the fs block size is larger than the >> device's logical block size, which should cover a 4k device block >> size with a 16k fs block size. >> >> I verified that the patched test does not run on my 4k sector >> device with a 4k file system. I also verified that it continues to >> run on a 512 byte logical sector device with a 4k file system block >> size. >> Signed-off-by: Jeff Moyer <jmoyer@xxxxxxxxxx> >> Signed-off-by: Christoph Hellwig <hch@xxxxxx> > > The name was added in this commit, and the message would lead me to > believe that Jeff intended for the test to not run on a 4k physical > sector disk with a 4k fs, so is the "logical_block_size" name a > misnomer? Well, it wants to be able to do sub-fs-block-sized direct IO. Jeff assumed that the DIO limitation would be logical block size, but the mkfs commit I referenced changed the limit to physical block size, which I think is a mistake, in retrospect. At least for the buftarg sector sizes, we should probably set it to logical sector size, to allow smaller DIOs if requested. Let me give that some thought. -Eric _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
