Because scsi_finish_command() subtracts the residual from the buffer length, residual overflows must not be reported. Reflect this in the SCSI documentation. See also commit 9237f04e12cc ("scsi: core: Fix scsi_get/set_resid() interface")
Cc: Damien Le Moal dlemoal@kernel.org Cc: Hannes Reinecke hare@suse.de Cc: Douglas Gilbert dgilbert@interlog.com Cc: stable@vger.kernel.org Signed-off-by: Bart Van Assche bvanassche@acm.org --- Documentation/scsi/scsi_mid_low_api.rst | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/Documentation/scsi/scsi_mid_low_api.rst b/Documentation/scsi/scsi_mid_low_api.rst index 6fa3a6279501..022198c51350 100644 --- a/Documentation/scsi/scsi_mid_low_api.rst +++ b/Documentation/scsi/scsi_mid_low_api.rst @@ -1190,11 +1190,11 @@ Members of interest: - pointer to scsi_device object that this command is associated with. resid - - an LLD should set this signed integer to the requested + - an LLD should set this unsigned integer to the requested transfer length (i.e. 'request_bufflen') less the number of bytes that are actually transferred. 'resid' is preset to 0 so an LLD can ignore it if it cannot detect - underruns (overruns should be rare). If possible an LLD + underruns (overruns should not be reported). An LLD should set 'resid' prior to invoking 'done'. The most interesting case is data transfers from a SCSI target device (e.g. READs) that underrun.