Hi Zhen, On 2015/9/9 13:16, Zhen Ren wrote: > Hi Yiwen, > > I try to reproduce this case, but it didn't act like you describe. > What I did: > === > laptop:/mnt/shared # mount | grep ocfs2 > ocfs2_dlmfs on /dlm type ocfs2_dlmfs (rw,relatime) > /dev/sda3 on /mnt/shared type ocfs2 > (rw,relatime,_netdev,heartbeat=local,nointr,data=ordered,errors=remount-ro,atime_quantum=60,coherency=full,user_xattr,acl) > laptop:/mnt/shared # dd if=/dev/zero of=/mnt/shared/hello bs=512 count=1 > oflag=direct > 1+0 records in > 1+0 records out > 512 bytes (512 B) copied, 0.000684382 s, 748 kB/s > laptop:/mnt/shared # truncate hello -s 2097152 > laptop:/mnt/shared # cat hello ======> nothing I don't think 'cat' works here. Could you please use hexdump?
> laptop:/mnt/shared # uname -r > 3.16.7-21-desktop > === > > Did I do something wrong? If I misunderstand, please correct me. > Thanks. > > >>> >> A simplified test case is (this case from Ryan): >> 1) dd if=/dev/zero of=/mnt/hello bs=512 count=1 oflag=direct; >> 2) truncate /mnt/hello -s 2097152 >> file 'hello' is not exist before test. After this command, >> file 'hello' should be all zero. But 512~4096 is some random data. >> >> Setting bh state to new when get a new block, if so, >> direct_io_worker()->dio_zero_block() will fill-in the unused portion >> of the block with zero. >> >> Signed-off-by: Yiwen Jiang <jiangyi...@huawei.com> >> --- >> fs/ocfs2/aops.c | 1 + >> 1 file changed, 1 insertion(+) >> >> diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c >> index 1a35c61..bd106b9 100644 >> --- a/fs/ocfs2/aops.c >> +++ b/fs/ocfs2/aops.c >> @@ -581,6 +581,7 @@ static int ocfs2_direct_IO_get_blocks(struct inode >> *inode, sector_t iblock, >> ret = -EIO; >> goto bail; >> } >> + set_buffer_new(bh_result); >> } >> >> /* > > > > > -- > Eric, Ren > > > > > _______________________________________________ > Ocfs2-devel mailing list > Ocfs2-devel@oss.oracle.com > https://oss.oracle.com/mailman/listinfo/ocfs2-devel > > _______________________________________________ Ocfs2-devel mailing list Ocfs2-devel@oss.oracle.com https://oss.oracle.com/mailman/listinfo/ocfs2-devel
