From: Nicholas Bellinger <[email protected]> This patch resets se_cmd->data_length for COMPARE_AND_WRITE emulation within sbc_compare_and_write() to NoLB * block_size in order to address a bug with FILEIO backends where a I/O failure will occur when data_length does not match the I/O size being actually dispatched for the individual per block READs + WRITEs.
This is done late enough in sbc_compare_and_write() after the memory allocations have occured in transport_generic_new_cmd() to not cause any unwanted side-effects. Reported-by: Thomas Glanzmann <[email protected]> Cc: Thomas Glanzmann <[email protected]> Signed-off-by: Nicholas Bellinger <[email protected]> --- drivers/target/target_core_sbc.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/target/target_core_sbc.c b/drivers/target/target_core_sbc.c index 6c17295..a9dca11 100644 --- a/drivers/target/target_core_sbc.c +++ b/drivers/target/target_core_sbc.c @@ -508,6 +508,12 @@ sbc_compare_and_write(struct se_cmd *cmd) cmd->transport_complete_callback = NULL; return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; } + /* + * Reset cmd->data_length to individual block_size in order to not + * confuse backend drivers that depend on this value matching the + * size of the I/O being submitted. + */ + cmd->data_length = cmd->t_task_nolb * dev->dev_attrib.block_size; ret = cmd->execute_rw(cmd, cmd->t_bidi_data_sg, cmd->t_bidi_data_nents, DMA_FROM_DEVICE); -- 1.8.4.rc3 -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
