scsi: target: iscsi: Rename iscsi_session to iscsit_session

The structure iscsi_session naming is used by the iSCSI initiator
driver. Rename the target session to iscsit_session to have more readable
code.

Link: https://lore.kernel.org/r/20220428092939.36768-3-mgurtovoy@nvidia.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: iscsi: Rename iscsi_conn to iscsit_conn

The structure iscsi_conn naming is used by the iSCSI initiator
driver. Rename the target conn to iscsit_conn to have more readable code.

Link: https://lore.kernel.org/r/20220428092939.36768-2-mgurtovoy@nvidia.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: iscsi: Rename iscsi_cmd to iscsit_cmd

The structure iscsi_cmd naming is used by the iSCSI initiator driver.
Rename the target cmd to iscsit_cmd to have more readable code.

Link: https://lore.kernel.org/r/20220428092939.36768-1-mgurtovoy@nvidia.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: iscsi: Avoid in_interrupt() usage in iscsit_close_session()

iscsit_close_session() uses in_interrupt() to decide if it needs to check
the return value of iscsit_check_session_usage_count() if it was not able
to sleep.

The usage of in_interrupt() in drivers is phased out and Linus clearly
requested that code which changes behaviour depending on context should
either be separated or the context be conveyed in an argument passed by the
caller, which usually knows the context.

iscsit_close_session() has two callers:

- iscsit_handle_time2retain_timeout()
A timer_list callback.

- iscsit_close_connection()
Runs in preemptible context, acquires a mutex.

Add an argument to iscsit_close_session() indicating if sleeping is
possible.

Link: https://lore.kernel.org/r/20201220203638.43615-2-bigeasy@linutronix.de
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: remove boilerplate code

iscsit_free_session() is equivalent to iscsit_stop_session() followed by a
call to iscsit_close_session().

Link: https://lore.kernel.org/r/20200313170656.9716-2-mlombard@redhat.com
Tested-by: Rahul Kundu <rahul.kundu@chelsio.com>
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target/iscsi: Fix spelling of "unsolicited"

Change "unsoliticed" into "unsolicited".

Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Cc: Mike Christie <mchristi@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

target/iscsi: Allocate session IDs from an IDA

Since the session is never looked up by ID, we can use the more
space-efficient IDA instead of the IDR.

Signed-off-by: Matthew Wilcox <willy@infradead.org>

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

target: Minimize #include directives

Remove superfluous #include directives from the include/target/*.h
files. Add missing #include directives to other *.h and *.c files.
Use forward declarations for structures where possible. This
change reduces the build time for make M=drivers/target on my
laptop from 27.1s to 18.7s or by about 30%.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Bryant G. Ly <bryantly@linux.vnet.ibm.com>

target/iscsi: Replace __kernel_sockaddr_storage with sockaddr_storage

It appears to be what the rest of the kernel does, so let's do it too.

Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

target/iscsi: Fix np_ip bracket issue by removing np_ip

Revert commit 1997e6259, which causes double brackets on ipv6
inaddr_any addresses.

Since we have np_sockaddr, if we need a textual representation we can
use "%pISc".

Change iscsit_add_network_portal() and iscsit_add_np() signatures to remove
*ip_str parameter.

Fix and extend some comments earlier in the function.

Tested to work for :: and ::1 via iscsiadm, previously :: failed, see
https://bugzilla.redhat.com/show_bug.cgi?id=1249107 .

CC: stable@vger.kernel.org
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

target: simplify the target template registration API

Instead of calling target_fabric_configfs_init() +
target_fabric_configfs_register() / target_fabric_configfs_deregister()
target_fabric_configfs_free() from every target driver, rewrite the API
so that we have simple register/unregister functions that operate on
a const operations vector.

This patch also fixes a memory leak in several target drivers. Several
target drivers namely called target_fabric_configfs_deregister()
without calling target_fabric_configfs_free().

A large part of this patch is based on earlier changes from
Bart Van Assche <bart.vanassche@sandisk.com>.

(v2: Add a new TF_CIT_SETUP_DRV macro so that the core configfs code
can declare attributes as either core only or for drivers)

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

iscsi/iser-target: Convert to command priv_size usage

This command converts iscsi/isert-target to use allocations based on
iscsit_transport->priv_size within iscsit_allocate_cmd(), instead of
using an embedded isert_cmd->iscsi_cmd.

This includes removing iscsit_transport->alloc_cmd() usage, along
with updating isert-target code to use iscsit_priv_cmd().

Also, remove left-over iscsit_transport->release_cmd() usage for
direct calls to iscsit_release_cmd(), and drop the now unused
lio_cmd_cache and isert_cmd_cache.

Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Kent Overstreet <kmo@daterainc.com>
Signed-off-by: Nicholas Bellinger <nab@daterainc.com>

iscsi-target: Prepare login code for multi-plexing support

This patch prepares the iscsi-target login code for multi-plexing
support. This includes:

- Adding iscsi_tpg_np->tpg_np_kref + iscsit_login_kref_put() for
handling callback of iscsi_tpg_np->tpg_np_comp
- Adding kref_put() in iscsit_deaccess_np()
- Adding kref_put() and wait_for_completion() in
iscsit_reset_np_thread()
- Refactor login failure path release logic into
iscsi_target_login_sess_out()
- Update __iscsi_target_login_thread() to handle
iscsi_post_login_handler() asynchronous completion
- Add shutdown parameter for iscsit_clear_tpg_np_login_thread*()

v3 changes:
- Convert iscsi_portal_group->np_login_lock to ->np_login_sem
- Add LOGIN_FLAGS definitions

v2 changes:
- Remove duplicate call to iscsi_post_login_handler() in
__iscsi_target_login_thread()
- Drop unused iscsi_np->np_login_tpg

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

iscsi-target: Fix iscsit_add_reject* usage for iser

This patch changes iscsit_add_reject() + iscsit_add_reject_from_cmd()
usage to not sleep on iscsi_cmd->reject_comp to address a free-after-use
usage bug in v3.10 with iser-target code.

It saves ->reject_reason for use within iscsit_build_reject() so the
correct value for both transport cases. It also drops the legacy
fail_conn parameter usage throughput iscsi-target code and adds
two iscsit_add_reject_cmd() and iscsit_reject_cmd helper functions,
along with various small cleanups.

(v2: Re-enable target_put_sess_cmd() to be called from
iscsit_add_reject_from_cmd() for rejects invoked after
target_get_sess_cmd() has been called)

Cc: Or Gerlitz <ogerlitz@mellanox.com>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

iscsi-target: Refactor RX PDU logic + export request PDU handling

This patch refactors existing traditional iscsi RX side PDU handling
to use iscsit_transport, and exports the necessary logic for external
transport modules.

This includes:

- Refactor iscsit_handle_scsi_cmd() into PDU setup / processing
- Add updated iscsit_handle_scsi_cmd() for tradtional iscsi code
- Add iscsit_set_unsoliticed_dataout() wrapper
- Refactor iscsit_handle_data_out() into PDU check / processing
- Add updated iscsit_handle_data_out() for tradtional iscsi code
- Add iscsit_handle_nop_out() + iscsit_handle_task_mgt_cmd() to
accept pre-allocated struct iscsi_cmd
- Add iscsit_build_r2ts_for_cmd() caller for iscsi_target_transport
to handle ISTATE_SEND_R2T for TX immediate queue
- Refactor main traditional iscsi iscsi_target_rx_thread() PDU switch
into iscsi_target_rx_opcode() using iscsit_allocate_cmd()
- Turn iscsi_target_rx_thread() process context into NOP for
ib_isert side work-queue.

v5 changes:

- Make iscsit_handle_scsi_cmd() static (Fengguang)
- Fix iscsit_handle_scsi_cmd() exception se_cmd leak (nab)

v3 changes:
- Add extra target_put_sess_cmd call in iscsit_add_reject_from_cmd
after completion

v2 changes:

- Disable iscsit_ack_from_expstatsn() usage for RDMAExtentions=Yes
- Disable iscsit_allocate_datain_req() usage for RDMAExtentions=Yes
- Add target_get_sess_cmd() reference counting to
iscsit_setup_scsi_cmd()
- Add TFO->lio_check_stop_free() fabric API caller
- Add export of iscsit_stop_dataout_timer() symbol
- Add iscsit_build_r2ts_for_cmd() for iscsit_transport->iscsit_get_dataout()
- Convert existing usage of iscsit_build_r2ts_for_cmd() to
->iscsit_get_dataout()
- Drop RDMAExtentions=Yes specific check in iscsit_build_r2ts_for_cmd()
- Fix RDMAExtentions -> RDMAExtensions typo (andy)
- Pass correct dump_payload value into iscsit_get_immediate_data()
for iscsit_handle_scsi_cmd()

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

iscsi-target: Refactor iscsit_get_np sockaddr matching into iscsit_check_np_match

This patch refactors the sockaddr matching logic in iscsit_get_np() into
a seperate iscsit_check_np_match() that can be used by external code.

Tested-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

iscsit: mark various functions static

This patch marks a number of functions static to appease sparse static
checking.

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

target/iscsi: Misc cleanups from Agrover (round 2)

This patch includes the handful of squashed patches for target/iscsi from
Andy's original series into lio-core/master code:

*) Make iscsit_add_reject static
*) Remove unused data_offset_end from iscsi_datain_req
*) Remove "#if 0" stubs
*) Rename iscsi_datain_req to cmd_datain_node
*) Cleanups for built_r2ts_for_cmd()
*) Cleanups for Cleanup build_sendtargets_response()

Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

target/iscsi: Refactor target_tx_thread immediate+response queue loops

Immediate queue:

Consolidate down to one switch statement by moving send_tx_data and stuff
from second switch into the first switch, or the functions the first switch
calls.

Response queue:

Do not lock istate_lock except directly around i_state modifications.

Put entire ISTATE_SEND_DATAIN path within first switch statement, in prep
for further refactoring.

All other cases set use_misc = 1 and will not be using sendpage, so just
use send_tx_data for these and set use_misc param to 1.

map_sg, sent_status, use_misc, and se_cmd vars no longer needed.

Then put immediate and response handling in separate functions in order
to get iscsi_target_tx_thread down to where it fits on a page.

Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

iscsi-target: Add iSCSI fabric support for target v4.1

The Linux-iSCSI.org target module is a full featured in-kernel
software implementation of iSCSI target mode (RFC-3720) for the
current WIP mainline target v4.1 infrastructure code for the v3.1
kernel. More information can be found here:

http://linux-iscsi.org/wiki/ISCSI

This includes support for:

* RFC-3720 defined request / response state machines and support for
all defined iSCSI operation codes from Section 10.2.1.2 using libiscsi
include/scsi/iscsi_proto.h PDU definitions
* Target v4.1 compatible control plane using the generic layout in
target_core_fabric_configfs.c and fabric dependent attributes
within /sys/kernel/config/target/iscsi/ subdirectories.
* Target v4.1 compatible iSCSI statistics based on RFC-4544 (iSCSI MIBS)
* Support for IPv6 and IPv4 network portals in M:N mapping to TPGs
* iSCSI Error Recovery Hierarchy support
* Per iSCSI connection RX/TX thread pair scheduling affinity
* crc32c + crc32c_intel SSEv4 instruction offload support using libcrypto
* CHAP Authentication support using libcrypto
* Conversion to use internal SGl allocation with iscsit_alloc_buffs() ->
transport_generic_map_mem_to_cmd()

(nab: Fix iscsi_proto.h struct scsi_lun usage from linux-next in commit:
iscsi: Use struct scsi_lun in iscsi structs instead of u8[8])
(nab: Fix 32-bit compile warnings)

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andy Grover <agrover@redhat.com>
Acked-by: Roland Dreier <roland@kernel.org>
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>