usb: gadget: f_tcm: Remove snprintf() from sysfs call-backs and replace with sysfs_emit()

Since snprintf() has the documented, but still rather strange trait of
returning the length of the data that *would have been* written to the
array if space were available, rather than the arguably more useful
length of data *actually* written, it is usually considered wise to use
something else instead in order to avoid confusion.

In the case of sysfs call-backs, new wrappers exist that do just that.

This patch replaces just one use of snprintf() found in the sysfs
.show() call-back with the new sysfs_emit() helper.

Link: https://lwn.net/Articles/69419/
Link: https://github.com/KSPP/linux/issues/105
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Dmitry Bogdanov <d.bogdanov@yadro.com>
Cc: linux-usb@vger.kernel.org
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20231130105459.3208986-6-lee@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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

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 <michael.christie@oracle.com>
Link: https://lore.kernel.org/r/20230928020907.5730-2-michael.christie@oracle.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

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

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 <michael.christie@oracle.com>
Link: https://lore.kernel.org/r/20230319015620.96006-4-michael.christie@oracle.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: usb: gadget: f_tcm: Remove default fabric ops callouts

Remove callouts that are identical to the default implementations in TCM
Core.

Signed-off-by: Dmitry Bogdanov <d.bogdanov@yadro.com>
Link: https://lore.kernel.org/r/20230313181110.20566-8-d.bogdanov@yadro.com
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

usb: gadget: add _init/__exit annotations to module init/exit funcs

Add missing _init/__exit annotations to module init/exit funcs.

Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com>
Link: https://lore.kernel.org/r/20220917084413.23957-1-xiujianfeng@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

scsi: target: usb: Replace enable attr with ops.enable

Remove tpg/enable attribute. Add fabric ops enable_tpg implementation
instead.

Link: https://lore.kernel.org/r/20210910084133.17956-8-d.bogdanov@yadro.com
Reviewed-by: Roman Bolshakov <r.bolshakov@yadro.com>
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Dmitry Bogdanov <d.bogdanov@yadro.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

usb: fix various gadgets null ptr deref on 10gbps cabling.

This avoids a null pointer dereference in
f_{ecm,eem,hid,loopback,printer,rndis,serial,sourcesink,subset,tcm}
by simply reusing the 5gbps config for 10gbps.

Fixes: eaef50c76057 ("usb: gadget: Update usb_assign_descriptors for SuperSpeedPlus")
Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: Lorenzo Colitti <lorenzo@google.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Michael R Sweet <msweet@msweet.org>
Cc: Mike Christie <michael.christie@oracle.com>
Cc: Pawel Laszczak <pawell@cadence.com>
Cc: Peter Chen <peter.chen@nxp.com>
Cc: Sudhakar Panneerselvam <sudhakar.panneerselvam@oracle.com>
Cc: Wei Ming Chen <jj251510319013@gmail.com>
Cc: Will McVicker <willmcvicker@google.com>
Cc: Zqiang <qiang.zhang@windriver.com>
Reviewed-By: Lorenzo Colitti <lorenzo@google.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Link: https://lore.kernel.org/r/20210608044141.3898496-1-zenczykowski@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

scsi: target: usb: gadget: Convert to new submission API

target_submit_cmd() is now only for simple drivers that do their own sync
during shutdown and do not use target_stop_session(). It will never return
a failure, so we can remove that code from the driver.

Note: Before these patches target_submit_cmd() would never return an error
for usb since it does not use target_stop_session(). If it did then we
would have hit a refcount error here:

transport_send_check_condition_and_sense(se_cmd,
TCM_UNSUPPORTED_SCSI_OPCODE, 1);
transport_generic_free_cmd(&cmd->se_cmd, 0);

transport_send_check_condition_and_sense() calls queue_status and the
driver can sometimes do transport_generic_free_cmd() from there via
uasp_status_data_cmpl(). In that case, the above
transport_generic_free_cmd() would then hit a refcount error.

So that other use of the above error path in the driver is also probably
wrong, but someone with the hardware needs to fix that.

Link: https://lore.kernel.org/r/20210227170006.5077-11-michael.christie@oracle.com
Cc: Felipe Balbi <balbi@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: core: Rename transport_init_se_cmd()

Rename transport_init_se_cmd() to __target_init_cmd() to reflect that it is
more of an internal function that drivers should normally not use and
because we are going to add a new init function in the next patches.

Link: https://lore.kernel.org/r/20210227170006.5077-4-michael.christie@oracle.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

usb: gadget: config_ep_by_speed_and_alt instead of config_ep_by_speed

This patch replace config_ep_by_speed with config_ep_by_speed_and_alt.
This change allows to select proper usb_ss_ep_comp_descriptor for each
stream capable endpoints.

f_tcm function for SS use array of headers for both BOT/UAS alternate
setting:

static struct usb_descriptor_header *uasp_ss_function_desc[] = {
(struct usb_descriptor_header *) &bot_intf_desc,
(struct usb_descriptor_header *) &uasp_ss_bi_desc,
(struct usb_descriptor_header *) &bot_bi_ep_comp_desc,
(struct usb_descriptor_header *) &uasp_ss_bo_desc,
(struct usb_descriptor_header *) &bot_bo_ep_comp_desc,

(struct usb_descriptor_header *) &uasp_intf_desc,
(struct usb_descriptor_header *) &uasp_ss_bi_desc,
(struct usb_descriptor_header *) &uasp_bi_ep_comp_desc,
(struct usb_descriptor_header *) &uasp_bi_pipe_desc,
(struct usb_descriptor_header *) &uasp_ss_bo_desc,
(struct usb_descriptor_header *) &uasp_bo_ep_comp_desc,
(struct usb_descriptor_header *) &uasp_bo_pipe_desc,
(struct usb_descriptor_header *) &uasp_ss_status_desc,
(struct usb_descriptor_header *) &uasp_status_in_ep_comp_desc,
(struct usb_descriptor_header *) &uasp_status_pipe_desc,
(struct usb_descriptor_header *) &uasp_ss_cmd_desc,
(struct usb_descriptor_header *) &uasp_cmd_comp_desc,
(struct usb_descriptor_header *) &uasp_cmd_pipe_desc,
NULL,
};

The first 5 descriptors are associated with BOT alternate setting,
and others are associated with UAS.

During handling UAS alternate setting f_tcm driver invokes
config_ep_by_speed and this function sets incorrect companion endpoint
descriptor in usb_ep object.

Instead setting ep->comp_desc to uasp_bi_ep_comp_desc function in this
case set ep->comp_desc to bot_uasp_ss_bi_desc.

And in result it uses the descriptor from BOT alternate setting
instead UAS.

Finally, it causes that controller driver during enabling endpoints
detect that just enabled endpoint for bot.

Signed-off-by: Jayshri Pawar <jpawar@cadence.com>
Signed-off-by: Pawel Laszczak <pawell@cadence.com>
Reviewed-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>

usb: gadget: f_tcm: Fix some resource leaks in some error paths

If a memory allocation fails within a 'usb_ep_alloc_request()' call, the
already allocated memory must be released.

Fix a mix-up in the code and free the correct requests.

Fixes: c52661d60f63 ("usb-gadget: Initial merge of target module for UASP + BOT")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Felipe Balbi <balbi@kernel.org>

usb: gadget: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20200707171500.GA13620@embeddedor
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

scsi: target: Initialize LUN in transport_init_se_cmd()

Initialization of orig_fe_lun is moved to transport_init_se_cmd() from
transport_lookup_cmd_lun(). This helps for the cases where the SCSI request
fails before the call to transport_lookup_cmd_lun() so that
trace_target_cmd_complete() can print the LUN information to the trace
buffer. Due to this change, the lun parameter is removed from
transport_lookup_cmd_lun() and transport_lookup_tmr_lun().

Link: https://lore.kernel.org/r/1591559913-8388-3-git-send-email-sudhakar.panneerselvam@oracle.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Sudhakar Panneerselvam <sudhakar.panneerselvam@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

usb: gadget: f_tcm: Inform last stream request

Set the request->is_last to each stream request to indicate that the
request is the last stream request of a transfer. The DWC3 controller
needs to know this info to properly switch streams. The current
implementation of f_tcm uses a single request per transfer, so every
stream request is the last of its stream.

Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>

usb: gadget: f_tcm: Provide support to get alternate setting in tcm function

Providing tcm_get_alt in tcm function to support Bulk only protocol and
USB Attached SCSI protocol

Signed-off-by: Jayshri Pawar <jpawar@cadence.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

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

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 <balbi@ti.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Reviewed-by: Andy Grover <agrover@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Cc: Mike Christie <mchristi@redhat.com>
Cc: Himanshu Madhani <himanshu.madhani@qlogic.com>
Cc: Quinn Tran <quinn.tran@qlogic.com>
Cc: Saurav Kashyap <saurav.kashyap@qlogic.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: replace fabric_ops.name with fabric_alias

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 <ddiss@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

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

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 <ddiss@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: loop, usb, vhost, xen: use target_remove_session

This converts drivers that were only calling transport_deregister_session
to use target_remove_session. The calling of
transport_deregister_session_configfs via target_remove_session for these
types of drivers is ok, because they were not exporting info from fields
like sess_acl_list, sess->se_tpg and sess->fabric_sess_ptr from configfs
accessible functions, so they will see no difference.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: rename target_alloc_session

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 <mchristi@redhat.com>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Chris Boot <bootc@bootc.net>
Cc: Bryant G. Ly <bryantly@linux.vnet.ibm.com>
Cc: Michael Cyr <mikecyr@linux.vnet.ibm.com>
Cc: <qla2xxx-upstream@qlogic.com>
Cc: Johannes Thumshirn <jth@kernel.org>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: Remove second argument from fabric_make_tpg()

Since most target drivers do not use the second fabric_make_tpg() argument
("group") and since it is trivial to derive the group pointer from the wwn
pointer, do not pass the group pointer to fabric_make_tpg().

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Mike Christie <mchristi@redhat.com>
Cc: Felipe Balbi <felipe.balbi@linux.intel.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: Convert target drivers to use sbitmap

The sbitmap and the percpu_ida perform essentially the same task,
allocating tags for commands. The sbitmap outperforms the percpu_ida as
documented here: https://lkml.org/lkml/2014/4/22/553

The sbitmap interface is a little harder to use, but being able to remove
the percpu_ida code and getting better performance justifies the additional
complexity.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com> # f_tcm
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: Abstract tag freeing

Introduce target_free_tag() and convert all drivers to use it.

Signed-off-by: Matthew Wilcox <willy@infradead.org>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

USB: gadget: function: remove redundant initialization of 'tv_nexus'

Pointer tv_nexus is being initialized a value and this is never read
and is later being updated with the same value. Remove the redundant
initialization so that the assignment to tv_nexus is performed later
and more local to when it is being read.

Cleans up clang warning:
drivers/usb/gadget/function/f_tcm.c:1097:25: warning: Value stored to
'tv_nexus' during its initialization is never read

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

USB: gadget: function: Remove redundant license text

Now that the SPDX tag is in all USB files, that identifies the license
in a specific and legally-defined manner. So the extra GPL text wording
can be removed as it is no longer needed at all.

This is done on a quest to remove the 700+ different ways that files in
the kernel describe the GPL license text. And there's unneeded stuff
like the address (sometimes incorrect) for the FSF which is never
needed.

No copyright headers or other non-license-description text was removed.

Cc: Oliver Neukum <oneukum@suse.com>
Cc: Johan Hovold <johan@kernel.org>
Cc: Jerry Zhang <zhangjerry@google.com>
Cc: John Keeping <john@metanate.com>
Cc: Krzysztof Opasiak <k.opasiak@samsung.com>
Cc: Abdulhadi Mohamed <abdulahhadi2@gmail.com>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Janusz Dziedzic <januszx.dziedzic@linux.intel.com>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Vincent Pelletier <plr.vincent@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: add SPDX identifiers to all remaining files in drivers/usb/

It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.

Update the drivers/usb/ and include/linux/usb* files with the correct
SPDX license identifier based on the license text in the file itself.
The SPDX identifier is a legally binding shorthand, which can be used
instead of the full boiler plate text.

This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Acked-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: gadget: f_tcm: mark expected switch fall-through

In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

Addresses-Coverity-ID: 703128
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: gadget: make config_item_type structures const

Make these structures const as they are only passed to the const
argument of the functions config_{group/item}_init_type_name.

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

usb: gadget: Correct usb EP argument for BOT status request

This patch corrects the argument in usb_ep_free_request as it is
mistakenly set to ep_out. It should be ep_in for status request.

Signed-off-by: Manish Narani <mnarani@xilinx.com>
Acked-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

usb: gadget: Fix second argument of percpu_ida_alloc()

Pass a task state as second argument to percpu_ida_alloc().

Fixes: commit 71e7ae8e1fb2 ("usb-gadget/tcm: Conversion to percpu_ida tag pre-allocation")
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Cc: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Felipe Balbi <felipe.balbi@linux.intel.com>

usb: gadget: f_tcm: out of bound access in usbg_drop_tpg

Commit dc8c46a5ae77 ("usb: gadget: f_tcm: convert to new function
interface with backward compatibility") introduced a possible out
of bounds memory access:

If tpg is not found in function usbg_drop_tpg,
tpg_instances[TPG_INSTANCES] is accessed.

Fixes: dc8c46a5ae77 ("usb: gadget: f_tcm: convert to new function interface with backward compatibility")
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

target: make close_session optional

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

target: make ->shutdown_session optional

Turns out the template and thus many drivers got the return value wrong:
0 means the fabrics driver needs to put a session reference, which no
driver except for the iSCSI target drivers did. Fortunately none of these
drivers supports explicit Node ACLs, so the bug was harmless.

Even without that only qla2xxx and iscsi every did real work in
shutdown_session, so get rid of the boilerplate code in all other
drivers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

usb-gadget/tcm: Convert to TARGET_SCF_ACK_KREF I/O krefs

This patch drops struct usbg_cmd->kref internal kref-erence
usage, for proper TARGET_SCF_ACK_KREF conversion.

Tested-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

usb-gadget/tcm: Conversion to percpu_ida tag pre-allocation

This patch converts usb-gadget target to use percpu_ida tag
pre-allocation for struct usbg_cmd descriptor, in order to
avoid fast-path struct usbg_cmd memory allocations.

Note by default this is currently hardcoded to 128.

Tested-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

target: Convert demo-mode only drivers to target_alloc_session

This patch converts existing loopback, usb-gadget, and
xen-scsiback demo-mode only fabric drivers to use the
new target_alloc_session API caller.

This includes adding a new alloc_session callback for
fabric driver internal nexus pointer assignments.

(Fixes for early for-next nexus breakage - Dan Carpenter)

Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Acked-by: Juergen Gross <jgross@suse.com>
Tested-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Tested-by: Chris Boot <bootc@bootc.net>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

usb: gadget: Update usb_assign_descriptors for SuperSpeedPlus

Add the 'ssp_descriptors' parameter to the usb_assign_descriptors()
function. This allows a function driver to add descriptors for
SuperSpeedPlus speeds if it supports it.

Also update all uses of this function in the gadget subsystem so that
they pass NULL for the ssp_descriptors parameters.

Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>

usb/gadget: Remove set-but-not-used variables

Avoid that building with W=1 triggers compiler warnings about
set-but-not-used variables.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Andy Grover <agrover@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

usb: gadget: f_tcm: add configfs support

Allow using the tcm function as a component of a gadget composed with
ConfigFS.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

usb: gadget: f_tcm: use usb_gstrings_attach

Do not directly use file static strings definitions in instances of f_tcm.
Instead use usb_gstrings_attach.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

usb: gadget: f_tcm: remove redundant singleton

The only instance is guaranteed with TPG_INSTANCES defined to 1.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

usb: gadget: f_tcm: remove compatibility layer

There are no old function interface users left.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

usb: gadget: f_tcm: convert to new function interface with backward compatibility

Converting tcm to the new function interface requires converting
USB tcm's function code and its users.

This patch converts the f_tcm.c to the new function interface.

The file can be now compiled into a separate module usb_f_tcm.ko.

The old function interface is provided by means of preprocessor conditional
directives. After all users are converted, the old interface can be
removed.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

usb: gadget: tcm: factor out f_tcm

Prepare for converting tcm to new function registration interface.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>