kernel/linux.git/include/target/target_core_fabric.h, branch linux-7.0.y

scsi: target: core: Unexport target_queue_submission()

2023-10-13T19:53:58+00:00

target_queue_submission() is not called by drivers anymore so unexport it. Signed-off-by: Mike Christie Link: https://lore.kernel.org/r/20230928020907.5730-7-michael.christie@oracle.com Signed-off-by: Martin K. Petersen

scsi: target: core: Kill transport_handle_cdb_direct()

2023-10-13T19:53:58+00:00

Move the code from transport_handle_cdb_direct() to target_submit() and have iSCSI call target_submit(). Signed-off-by: Mike Christie Link: https://lore.kernel.org/r/20230928020907.5730-5-michael.christie@oracle.com Signed-off-by: Martin K. Petersen

scsi: target: core: Move core_alua_check_nonop_delay() call

2023-10-13T19:53:57+00:00

Move core_alua_check_nonop_delay() to transport_handle_cdb_direct() so the iSCSI target driver doesn't have to call as many core functions directly. We will eventually merge transport_handle_cdb_direct and target_submit so iSCSI and the other drivers call a common function. It will also be helpful as preparation for future changes which allow the iSCSI target to defer command submission to the LIO submission workqueue, because we will have a common submission function for that which will be based on transport_handle_cdb_direct()/target_submit(). Signed-off-by: Mike Christie Link: https://lore.kernel.org/r/20230928020907.5730-3-michael.christie@oracle.com Signed-off-by: Martin K. Petersen

scsi: target: Have drivers report if they support direct submissions

2023-10-13T19:53:57+00:00

In some cases, like with multiple LUN targets or where the target has to respond to transport level requests from the receiving context it can be better to defer cmd submission to a helper thread. If the backend driver blocks on something like request/tag allocation it can block the entire target submission path and other LUs and transport IO on that session. In other cases like single LUN targets with storage that can support all the commands that the target can queue, then it's best to submit the cmd to the backend from the target's cmd receiving context. Subsequent commits will allow the user to config what they prefer, but drivers like loop can't directly submit because they can be called from a context that can't sleep. And, drivers like vhost-scsi can support direct submission, but need to keep their default behavior of deferring execution to avoid possible regressions where the backend can block. Make the drivers tell LIO core if they support direct submissions and their current default, so we can prevent users from misconfiguring the system and initialize devices correctly. Signed-off-by: Mike Christie Link: https://lore.kernel.org/r/20230928020907.5730-2-michael.christie@oracle.com Signed-off-by: Martin K. Petersen

scsi: target: iscs: Make write_pending_must_be_called a bit field

2023-10-13T19:53:57+00:00

Subsequent commits add more on/off type of settings to the target_core_fabric_ops struct so this makes write_pending_must_be_called a bit field instead of a bool to better organize the settings. Signed-off-by: Mike Christie Link: https://lore.kernel.org/r/20230928020907.5730-1-michael.christie@oracle.com Signed-off-by: Martin K. Petersen

scsi: target: iscsit: isert: Alloc per conn cmd counter

2023-03-24T21:32:23+00:00

This has iscsit allocate a per conn cmd counter and converts iscsit/isert to use it instead of the per session one. Signed-off-by: Mike Christie Link: https://lore.kernel.org/r/20230319015620.96006-5-michael.christie@oracle.com Signed-off-by: Martin K. Petersen

scsi: target: Pass in cmd counter to use during cmd setup

2023-03-24T21:32:23+00:00

Allow target_get_sess_cmd() users to pass in the cmd counter they want to use. Right now we pass in the session's cmd counter but in a subsequent commit iSCSI will switch from per session to per conn. Signed-off-by: Mike Christie Link: https://lore.kernel.org/r/20230319015620.96006-4-michael.christie@oracle.com Signed-off-by: Martin K. Petersen

scsi: target: Move cmd counter allocation

2023-03-24T21:32:23+00:00

iSCSI needs to allocate its cmd counter per connection for MCS support where we need to stop and wait on commands running on a connection instead of per session. This moves the cmd counter allocation to target_setup_session() which is used by drivers that need the stop+wait behavior per session. xcopy doesn't need stop+wait at all, so we will be OK moving the cmd counter allocation outside of transport_init_session(). Signed-off-by: Mike Christie Link: https://lore.kernel.org/r/20230319015620.96006-3-michael.christie@oracle.com Signed-off-by: Martin K. Petersen

scsi: target: core: Add common tpg/enable attribute

2021-10-05T03:27:38+00:00

Many fabric modules provide their own implementation of enable attribute in tpg. Provide a way to remove code duplication in the fabric modules and automatically add "enable" attribute if a fabric module has an implementation of fabric_enable_tpg(). Link: https://lore.kernel.org/r/20210910084133.17956-2-d.bogdanov@yadro.com Reviewed-by: Roman Bolshakov Reviewed-by: Mike Christie Signed-off-by: Dmitry Bogdanov Signed-off-by: Martin K. Petersen

scsi: target: core: Add workqueue based cmd submission

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

loop and vhost/scsi do their target cmd submission from driver workqueues. This allows them to avoid an issue where the backend may block waiting for resources like tags/requests, mem/locks, etc and that ends up blocking their entire submission path and for the case of vhost-scsi both the submission and completion path. This patch adds a helper drivers can use to submit from a LIO workqueue. This code will then be extended in the next patches to fix the plugging of backend devices. We are only converting vhost/loop initially, but the workqueue based submission will work for other drivers and have similar benefits where the main target loops will not end up blocking one some backend resource. Link: https://lore.kernel.org/r/20210227170006.5077-17-michael.christie@oracle.com Tested-by: Laurence Oberman Reviewed-by: Bodo Stroesser Signed-off-by: Mike Christie Signed-off-by: Martin K. Petersen