linux.git/drivers/vhost/scsi.c, branch v5.19

vhost: rename vhost_work_dev_flush

2022-05-31T16:45:10+00:00

This patch renames vhost_work_dev_flush to just vhost_dev_flush to
relfect that it flushes everything on the device and that drivers
don't know/care that polls are based on vhost_works. Drivers just
flush the entire device and polls, and works for vhost-scsi
management TMFs and IO net virtqueues, etc all are flushed.

Signed-off-by: Mike Christie 
Acked-by: Jason Wang 
Reviewed-by: Stefano Garzarella 
Message-Id: <20220517180850.198915-9-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin

vhost-scsi: drop flush after vhost_dev_cleanup

2022-05-31T16:45:10+00:00

The flush after vhost_dev_cleanup is not needed because:

1. It doesn't do anything. vhost_dev_cleanup will stop the worker thread
so the flush call will just return since the worker has not device.

2. It's not needed for the re-queue case. vhost_scsi_evt_handle_kick grabs
the mutex and if the backend is NULL will return without queueing a work.
vhost_scsi_clear_endpoint will set the backend to NULL under the vq->mutex
then drops the mutex and does a flush. So we know when
vhost_scsi_clear_endpoint has dropped the mutex after clearing the backend
no evt related work will be able to requeue. The flush would then make sure
any queued evts are run and return.

Signed-off-by: Mike Christie 
Acked-by: Jason Wang 
Message-Id: <20220517180850.198915-7-michael.christie@oracle.com>
Signed-off-by: Michael S. Tsirkin

vhost scsi: Convert to SPDX identifier

2021-09-05T20:23:08+00:00

use SPDX-License-Identifier instead of a verbose license text

Signed-off-by: Cai Huoqing 
Link: https://lore.kernel.org/r/20210821123320.734-1-caihuoqing@baidu.com
Signed-off-by: Michael S. Tsirkin 
Reviewed-by: Stefan Hajnoczi

vhost-scsi: reduce flushes during endpoint clearing

2021-07-03T08:50:54+00:00

vhost_scsi_flush will flush everything, so we can clear the backends then
flush, then destroy. We don't need to flush before each vq destruction
because after the flush we will have made sure there can be no new cmds
started and there are no running cmds.

Signed-off-by: Mike Christie 
Link: https://lore.kernel.org/r/20210525174733.6212-4-michael.christie@oracle.com
Signed-off-by: Michael S. Tsirkin

vhost-scsi: remove extra flushes

2021-07-03T08:50:54+00:00

The vhost work flush function was flushing the entire work queue, so
there is no need for the double vhost_work_dev_flush calls in
vhost_scsi_flush.

And we do not need to call vhost_poll_flush for each poller because
that call also ends up flushing the same work queue thread the
vhost_work_dev_flush call flushed.

Signed-off-by: Mike Christie 
Reviewed-by: Stefan Hajnoczi 
Acked-by: Jason Wang 
Link: https://lore.kernel.org/r/20210525174733.6212-3-michael.christie@oracle.com
Signed-off-by: Michael S. Tsirkin

vhost: remove work arg from vhost_work_flush

2021-07-03T08:50:54+00:00

vhost_work_flush doesn't do anything with the work arg. This patch drops
it and then renames vhost_work_flush to vhost_work_dev_flush to reflect
that the function flushes all the works in the dev and not just a
specific queue or work item.

Signed-off-by: Mike Christie 
Acked-by: Jason Wang 
Reviewed-by: Chaitanya Kulkarni 
Link: https://lore.kernel.org/r/20210525174733.6212-2-michael.christie@oracle.com
Reviewed-by: Stefano Garzarella 
Signed-off-by: Michael S. Tsirkin

scsi: target: vhost-scsi: Use LIO wq cmd submission helper

2021-03-04T22:37:02+00:00

Convert vhost-scsi to use the LIO wq cmd submission helper.

Link: https://lore.kernel.org/r/20210227170006.5077-18-michael.christie@oracle.com
Signed-off-by: Mike Christie 
Reviewed-by: Stefan Hajnoczi 
Signed-off-by: Martin K. Petersen

scsi: target: core: Add gfp_t arg to target_cmd_init_cdb()

2021-03-04T22:37:02+00:00

tcm_loop could be used like a normal block device, so we can't use
GFP_KERNEL and should use GFP_NOIO. This adds a gfp_t arg to
target_cmd_init_cdb() and converts the users. For every driver but loop
GFP_KERNEL is kept.

This will also be useful in subsequent patches where loop needs to do
target_submit_prep() from interrupt context to get a ref to the se_device,
and so it will need to use GFP_ATOMIC.

Link: https://lore.kernel.org/r/20210227170006.5077-16-michael.christie@oracle.com
Tested-by: Laurence Oberman 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Mike Christie 
Signed-off-by: Martin K. Petersen

scsi: target: vhost-scsi: Convert to new submission API

2021-03-04T22:37:01+00:00

target_submit_cmd_map_sgls() is being removed, so convert vhost-scsi to the
new submission API. This has it use target_init_cmd(),
target_submit_prep(), target_submit() because we need to have LIO core map
sgls which is now done in target_submit_prep(), and in the next patches we
will do the target_submit step from the LIO workqueue.

Note: vhost-scsi never calls target_stop_session() so
target_submit_cmd_map_sgls() never failed (in the new API target_init_cmd()
handles target_stop_session() being called when cmds are being
submitted). If it were to have used target_stop_session() and got an error,
we would have hit a refcount bug like xen and usb, because it does:

if (rc < 0) {
	transport_send_check_condition_and_sense(se_cmd,
			TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
	transport_generic_free_cmd(se_cmd, 0);
}

transport_send_check_condition_and_sense() calls queue_status which does
transport_generic_free_cmd(), and then we do an extra
transport_generic_free_cmd() call above which would have dropped the
refcount to -1 and the refcount code would spit out errors.

Link: https://lore.kernel.org/r/20210227170006.5077-12-michael.christie@oracle.com
Cc: "Michael S. Tsirkin" 
Cc: Stefan Hajnoczi 
Reviewed-by: Christoph Hellwig 
Reviewed-by: Stefan Hajnoczi 
Signed-off-by: Mike Christie 
Signed-off-by: Martin K. Petersen

scsi: sbitmap: Move allocation hint into sbitmap

2021-03-04T22:36:59+00:00

Allocation hint should have belonged to sbitmap. Also, when sbitmap's depth
is high and there is no need to use mulitple wakeup queues, user can
benefit from percpu allocation hint too.

Move allocation hint into sbitmap, then SCSI device queue can benefit from
allocation hint when converting to plain sbitmap.

Convert vhost/scsi.c to use sbitmap allocation with percpu alloc hint. This
is more efficient than the previous approach.

Link: https://lore.kernel.org/r/20210122023317.687987-5-ming.lei@redhat.com
Cc: Omar Sandoval 
Cc: Kashyap Desai 
Cc: Sumanesh Samanta 
Cc: Ewan D. Milne 
Cc: Mike Christie 
Cc: virtualization@lists.linux-foundation.org
Tested-by: Sumanesh Samanta 
Reviewed-by: Hannes Reinecke 
Signed-off-by: Ming Lei 
Signed-off-by: Martin K. Petersen