kernel/include/target/target_core_fabric.h, branch linux-5.1.y

scsi: target/core: Add target_send_busy()

2019-02-05T02:28:48Z

Introduce a function that sends the SCSI status "BUSY" back to the initiator. The next patch will add a call to this function in the srpt target driver. Reviewed-by: Hannes Reinecke Cc: Nicholas Bellinger Cc: Mike Christie Cc: Christoph Hellwig Signed-off-by: Bart Van Assche Signed-off-by: Martin K. Petersen

scsi: target/core: Remove the write_pending_status() callback function

2019-02-05T02:23:59Z

Due to the patch that makes TMF handling synchronous the write_pending_status() callback function is no longer called. Hence remove it. Acked-by: Felipe Balbi Reviewed-by: Sagi Grimberg Reviewed-by: Andy Grover Reviewed-by: Christoph Hellwig Reviewed-by: Hannes Reinecke Reviewed-by: Bryant G. Ly Cc: Nicholas Bellinger Cc: Mike Christie Cc: Himanshu Madhani Cc: Quinn Tran Cc: Saurav Kashyap Cc: Michael S. Tsirkin Cc: Juergen Gross Signed-off-by: Bart Van Assche Signed-off-by: Martin K. Petersen

scsi: target/core: Make ABORT and LUN RESET handling synchronous

2018-12-08T02:22:55Z

Instead of invoking target driver callback functions from the context that handles an abort or LUN RESET task management function, only set the abort flag from that context and perform the actual abort handling from the context of the regular command processing flow. This approach has the advantage that the task management code becomes much easier to read and to verify since the number of potential race conditions against the command processing flow is strongly reduced. This patch has been tested by running the following two shell commands concurrently for about ten minutes for both the iSCSI and the SRP target drivers ($dev is an initiator device node connected with storage provided by the target driver under test): * fio with data verification enabled on a filesystem mounted on top of $dev. * while true; do sg_reset -d $dev; echo -n .; sleep .1; done Cc: Nicholas Bellinger Cc: Mike Christie Cc: Christoph Hellwig Cc: David Disseldorp Cc: Hannes Reinecke Signed-off-by: Bart Van Assche Signed-off-by: Martin K. Petersen

scsi: target/core: Fix TAS handling for aborted commands

2018-12-08T02:22:15Z

The TASK ABORTED STATUS (TAS) bit is defined as follows in SAM: "TASK_ABORTED: this status shall be returned if a command is aborted by a command or task management function on another I_T nexus and the control mode page TAS bit is set to one". TAS handling is spread over the target core and the iSCSI target driver. If a LUN RESET is received, the target core will send the TASK_ABORTED response for all commands for which such a response has to be sent. If an ABORT TASK is received, only the iSCSI target driver will send the TASK_ABORTED response for the commands for which that response has to be sent. That is a bug since all target drivers have to honor the TAS bit. Fix this by moving the code that handles TAS from the iSCSI target driver into the target core. Additionally, if a command has been aborted, instead of sending the TASK_ABORTED status from the context that processes the SCSI command send it from the context of the ABORT TMF. The core_tmr_abort_task() change in this patch causes the CMD_T_TAS flag to be set if a TASK_ABORTED status has to be sent back to the initiator that submitted the command. If that flag has been set transport_cmd_finish_abort() will send the TASK_ABORTED response. Cc: Nicholas Bellinger Cc: Mike Christie Cc: Christoph Hellwig Cc: David Disseldorp Cc: Hannes Reinecke Signed-off-by: Bart Van Assche Signed-off-by: Martin K. Petersen

scsi: target/core: Simplify the code for aborting SCSI commands

2018-12-08T02:20:07Z

Instead of allowing the code that aborts a SCSI command to finish before all iSCSI data frames have been received, make that code wait until all iSCSI data frames have been received. Introduce a new member variable in the target driver template to communicate that information from the iSCSI target driver to the target core. This change allows to leave out the check whether or not it is already safe to send the TASK_ABORTED reply from transport_send_task_abort(). Cc: Nicholas Bellinger Cc: Mike Christie Cc: Christoph Hellwig Cc: David Disseldorp Cc: Hannes Reinecke Signed-off-by: Bart Van Assche Signed-off-by: Martin K. Petersen

scsi: target/core: Make sure that target_wait_for_sess_cmds() waits long enough

2018-12-08T02:20:07Z

A session must only be released after all code that accesses the session structure has finished. Make sure that this is the case by introducing a new command counter per session that is only decremented after the .release_cmd() callback has finished. This patch fixes the following crash: BUG: KASAN: use-after-free in do_raw_spin_lock+0x1c/0x130 Read of size 4 at addr ffff8801534b16e4 by task rmdir/14805 CPU: 16 PID: 14805 Comm: rmdir Not tainted 4.18.0-rc2-dbg+ #5 Call Trace: dump_stack+0xa4/0xf5 print_address_description+0x6f/0x270 kasan_report+0x241/0x360 __asan_load4+0x78/0x80 do_raw_spin_lock+0x1c/0x130 _raw_spin_lock_irqsave+0x52/0x60 srpt_set_ch_state+0x27/0x70 [ib_srpt] srpt_disconnect_ch+0x1b/0xc0 [ib_srpt] srpt_close_session+0xa8/0x260 [ib_srpt] target_shutdown_sessions+0x170/0x180 [target_core_mod] core_tpg_del_initiator_node_acl+0xf3/0x200 [target_core_mod] target_fabric_nacl_base_release+0x25/0x30 [target_core_mod] config_item_release+0x9c/0x110 [configfs] config_item_put+0x26/0x30 [configfs] configfs_rmdir+0x3b8/0x510 [configfs] vfs_rmdir+0xb3/0x1e0 do_rmdir+0x262/0x2c0 do_syscall_64+0x77/0x230 entry_SYSCALL_64_after_hwframe+0x49/0xbe Cc: Nicholas Bellinger Cc: Mike Christie Cc: Christoph Hellwig Cc: David Disseldorp Cc: Hannes Reinecke Signed-off-by: Bart Van Assche Signed-off-by: Martin K. Petersen

scsi: target: replace fabric_ops.name with fabric_alias

2018-11-28T23:50:59Z

iscsi_target_mod is the only LIO fabric where fabric_ops.name differs from the fabric_ops.fabric_name string. fabric_ops.name is used when matching target/$fabric ConfigFS create paths, so rename it .fabric_alias and fallback to target/$fabric vs .fabric_name comparison if .fabric_alias isn't initialised. iscsi_target_mod is the only fabric module to set .fabric_alias . All other fabric modules rely on .fabric_name matching and can drop the duplicate string. Signed-off-by: David Disseldorp Reviewed-by: Christoph Hellwig Signed-off-by: Martin K. Petersen

scsi: target: drop unnecessary get_fabric_name() accessor from fabric_ops

2018-11-28T23:50:58Z

All fabrics return a const string. In all cases *except* iSCSI the get_fabric_name() string matches fabric_ops.name. Both fabric_ops.get_fabric_name() and fabric_ops.name are user-facing, with the former being used for PR/ALUA state and the latter for ConfigFS (config/target/$name), so we unfortunately need to keep both strings around for now. Replace the useless .get_fabric_name() accessor function with a const string fabric_name member variable. Signed-off-by: David Disseldorp Reviewed-by: Christoph Hellwig Signed-off-by: Martin K. Petersen

scsi: target: add session removal function

2018-08-02T19:29:31Z

This adds a function to remove a session which should be used by drivers that use target_setup_session. The next patches will convert the target drivers to use this new function. Signed-off-by: Mike Christie Reviewed-by: Bart Van Assche Reviewed-by: Christoph Hellwig Cc: Chris Boot Cc: Bryant G. Ly Cc: Michael Cyr Cc: Cc: Johannes Thumshirn Cc: Felipe Balbi Cc: Sebastian Andrzej Siewior Cc: Andrzej Pietrasiewicz Cc: Michael S. Tsirkin Cc: Juergen Gross Signed-off-by: Martin K. Petersen

scsi: target: rename target_alloc_session

2018-08-02T19:29:31Z

Rename target_alloc_session to target_setup_session to avoid confusion with the other transport session allocation function that only allocates the session and because the target_alloc_session does so much more. It allocates the session, sets up the nacl and registers the session. The next patch will then add a remove function to match the setup in this one, so it should make sense for all drivers, except iscsi, to just call those 2 functions to setup and remove a session. iscsi will continue to be the odd driver. Signed-off-by: Mike Christie Reviewed-by: Bart Van Assche Reviewed-by: Christoph Hellwig Cc: Chris Boot Cc: Bryant G. Ly Cc: Michael Cyr Cc: Cc: Johannes Thumshirn Cc: Felipe Balbi Cc: Sebastian Andrzej Siewior Cc: Andrzej Pietrasiewicz Cc: Michael S. Tsirkin Cc: Juergen Gross Signed-off-by: Martin K. Petersen