Tao Ma wrote: > Hi Eric, > Thanks for the quick response. > > On 06/11/2010 12:08 PM, Eric Sandeen wrote: ... >> What are you using to call fiemap? Here it seems to be working: > I just wrote a simple test program by calling ioctl. It is attached. > btw, you need to call it immediately after dd so that we have a chance > that ext4 don't have time to allocate extents. ;) >> >> # dd if=/dev/zero of=testfile1 bs=1M count=1 seek=1; >> >> # filefrag -v testfile1 >> Filesystem type is: ef53 >> Filesystem cylinder groups is approximately 119 >> File size of testfile1 is 2097152 (512 blocks, blocksize 4096) >> ext logical physical expected length flags >> 0 256 151946 1 merged >> 1 257 151951 151946 2 merged >> 2 259 152434 151952 253 merged,eof >> testfile1: 4 extents found > I guess maybe filefrag use the diffrent ioctl flag, maybe > FIEMAP_FLAG_SYNC to let ext4 sync first. My tester isn't calling sync or using the sync flag, AFAIK. I'll take a look at yours. Thanks, -Eric > Regards, > Tao > -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
