linux.git/drivers/scsi/scsi_debug.c, branch v4.16

scsi: scsi_debug: delay stress fix

2018-01-17T06:00:05+00:00

Introduce a state enum into sdebug_defer objects to indicate which, if
any, defer method has been used with the associated command.  Also add 2
bools to indicate which of the defer methods has been initialized. Those
objects are re-used but the initialization only needs to be done
once. This simplifies command cancellation handling.

Now the delay associated with a deferred response of a command cannot be
changed (once started) by changing the delay (and ndelay) parameters in
sysfs. Command aborts and driver shutdown are still honoured immediately
when received.

[mkp: applied by hand]

Signed-off-by: Douglas Gilbert 
Reviewed-by: Bart Van Assche 
Signed-off-by: Martin K. Petersen

scsi: scsi_debug: add resp_write_scat function

2018-01-11T04:25:07+00:00

Add resp_write_scat() function to support decoding WRITE SCATTERED
(16 and 32). Also weave resp_write_scat() into the cdb decoding
logic.

Signed-off-by: Douglas Gilbert 
Signed-off-by: Martin K. Petersen

scsi: scsi_debug: ARRAY_SIZE and FF_MEDIA_IO

2018-01-11T04:25:06+00:00

Reviewer suggested using the ARRAY_SIZE macro. That reduced one of the subtle
inter-dependencies in the parser's tables.

It is important that commands which simulate media access, indicate this in the
flags for that command. The flag to do that was FF_DIRECT_IO. On reflection
FF_MEDIA_IO seems a more accurate description.

Signed-off-by: Douglas Gilbert 
Reviewed-by: Bart Van Assche 
Signed-off-by: Martin K. Petersen

scsi: scsi_debug: do_device_access add sg offset argument

2018-01-11T04:25:05+00:00

WRITE SCATTERED needs to take several "bites" out of the data-out buffer.
Expand the do_device_access() function to take a sg_skip argument.

Signed-off-by: Douglas Gilbert 
Reviewed-by: Bart Van Assche 
Signed-off-by: Martin K. Petersen

scsi: scsi_debug: fix group_number mask

2018-01-11T04:25:05+00:00

Various cdb masks incorrectly assumed the GROUP NUMBER field
was 5 bits long. It is actually 6 bits long. Correct.
Also fix mask failure (in same byte) to allow DLD0 in READ(16)
and WRITE(16).

Signed-off-by: Douglas Gilbert 
Reviewed-by: Bart Van Assche 
Signed-off-by: Martin K. Petersen

scsi: scsi_debug: tab, kstrto changes

2018-01-11T04:25:04+00:00

Some of my development tools tend to add spaces (my preference) rather
than tabs (kernel convention). Running unexpand to clean these spaces
up found more of them than checkpatch.pl did. Then checkpatch.pl
complained about other style violations in those newly tabbed lines.

Signed-off-by: Douglas Gilbert 
Reviewed-by: Bart Van Assche 
Signed-off-by: Martin K. Petersen

scsi: scsi_debug: Add support for injecting SCSI_MLQUEUE_HOST_BUSY

2017-12-08T02:50:51+00:00

Although it is important to be able to trigger the code in the SCSI core
for SCSI_MLQUEUE_HOST_BUSY handling, currently it is nontrivial to
trigger that code. Hence this patch that adds a new error injection
option to the scsi_debug driver for making the .queue_rq()
implementation of this driver return SCSI_MLQUEUE_HOST_BUSY.

Signed-off-by: Bart Van Assche 
Cc: Douglas Gilbert 
Cc: Christoph Hellwig 
Cc: Hannes Reinecke 
Cc: Johannes Thumshirn 
Acked-by: Douglas Gilbert 
Signed-off-by: Martin K. Petersen

scsi: scsi_debug: add cdb_len parameter

2017-12-08T02:06:59+00:00

While testing "sd: Micro-optimize READ / WRITE CDB encoding" patches it
was helpful to check various code paths associated with READ/WRITE 6, 10
and 16 byte cdb variants. There seems to be no user space "knobs" to
twiddle use_10_for_rw and friends in the scsi_device structure.  So add
a parameter to scsi_debug called "cdb_len" for this purpose.

[mkp: fixed typo]

Signed-off-by: Douglas Gilbert 
Reviewed-by: Bart Van Assche 
Signed-off-by: Martin K. Petersen

scsi: scsi_debug: remove jiffies_to_timespec

2017-12-05T01:32:55+00:00

There is no need to go through an intermediate timespec to convert to
ktime_t when we just want a simple multiplication. This gets rid of one
of the few users of jiffies_to_timespec, which I hope to remove as part
of the y2038 cleanup.

Signed-off-by: Arnd Bergmann 
Reviewed-by: Johannes Thumshirn 
Acked-by: Douglas Gilbert 
Signed-off-by: Martin K. Petersen

scsi: scsi_debug: write_same: fix error report

2017-10-31T16:28:05+00:00

The scsi_debug driver incorrectly suggests there is an error with the
SCSI WRITE SAME command when the number_of_logical_blocks is greater
than 1. It will also suggest there is an error when NDOB
(no data-out buffer) is set and the number_of_logical_blocks is
greater than 0. Both are valid, fix.

Signed-off-by: Douglas Gilbert 
Signed-off-by: Martin K. Petersen