There is a fatal bug that could easily cause data corruption when using
thin-provisioned blobs. In blob_request_submit_rw_iov(), we first get
lba by calling blob_calculate_lba_and_lba_count(),
blob_calculate_lba_and_lba_count() calculates different lbas according to
the return of bs_io_unit_is_allocated(). Later, we call bs_io_unit_is_allocated()
again to judge whether the specific cluster is allocated, the problem is it may
have be allocated here while not be allocated when calling blob_calculate_lba_and_lba_count()
before. To ensure the correctness of lba, we can do lba recalculation when
bs_io_unit_is_allocated() returns true, or make
blob_calculate_lba_and_lba_count() return the result of
bs_io_unit_is_allocated(), use the second solution in this patch.
By configuring more than one cpu core, md thread will run in a separate
SPDK thread, this data corruption scenario could be easily reproduced
by running fio verify in VMs using thin-provisioned Lvols as block
devices.
Signed-off-by: Sochin Jiang <jiangxiaoqing.sochin@bytedance.com>
Change-Id: I099865ff291ea42d5d49b693cc53f64b60881684
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/3318
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: Tomasz Zawadzki <tomasz.zawadzki@intel.com>