Commit graph

192 commits

Author SHA1 Message Date
Dmitry Bogdanov
168ed59170 scsi: target: core: Add TMF to tmr_list handling
[ Upstream commit 83ab68168a ]

An abort that is responded to by iSCSI itself is added to tmr_list but does
not go to target core. A LUN_RESET that goes through tmr_list takes a
refcounter on the abort and waits for completion. However, the abort will
be never complete because it was not started in target core.

 Unable to locate ITT: 0x05000000 on CID: 0
 Unable to locate RefTaskTag: 0x05000000 on CID: 0.
 wait_for_tasks: Stopping tmf LUN_RESET with tag 0x0 ref_task_tag 0x0 i_state 34 t_state ISTATE_PROCESSING refcnt 2 transport_state active,stop,fabric_stop
 wait for tasks: tmf LUN_RESET with tag 0x0 ref_task_tag 0x0 i_state 34 t_state ISTATE_PROCESSING refcnt 2 transport_state active,stop,fabric_stop
...
 INFO: task kworker/0:2:49 blocked for more than 491 seconds.
 task:kworker/0:2     state:D stack:    0 pid:   49 ppid:     2 flags:0x00000800
 Workqueue: events target_tmr_work [target_core_mod]
Call Trace:
 __switch_to+0x2c4/0x470
 _schedule+0x314/0x1730
 schedule+0x64/0x130
 schedule_timeout+0x168/0x430
 wait_for_completion+0x140/0x270
 target_put_cmd_and_wait+0x64/0xb0 [target_core_mod]
 core_tmr_lun_reset+0x30/0xa0 [target_core_mod]
 target_tmr_work+0xc8/0x1b0 [target_core_mod]
 process_one_work+0x2d4/0x5d0
 worker_thread+0x78/0x6c0

To fix this, only add abort to tmr_list if it will be handled by target
core.

Signed-off-by: Dmitry Bogdanov <d.bogdanov@yadro.com>
Link: https://lore.kernel.org/r/20240111125941.8688-1-d.bogdanov@yadro.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-03-01 13:16:43 +01:00
Junxiao Bi
77f82df960 scsi: target: core: Fix deadlock due to recursive locking
[ Upstream commit a154f5f643 ]

The following call trace shows a deadlock issue due to recursive locking of
mutex "device_mutex". First lock acquire is in target_for_each_device() and
second in target_free_device().

 PID: 148266   TASK: ffff8be21ffb5d00  CPU: 10   COMMAND: "iscsi_ttx"
  #0 [ffffa2bfc9ec3b18] __schedule at ffffffffa8060e7f
  #1 [ffffa2bfc9ec3ba0] schedule at ffffffffa8061224
  #2 [ffffa2bfc9ec3bb8] schedule_preempt_disabled at ffffffffa80615ee
  #3 [ffffa2bfc9ec3bc8] __mutex_lock at ffffffffa8062fd7
  #4 [ffffa2bfc9ec3c40] __mutex_lock_slowpath at ffffffffa80631d3
  #5 [ffffa2bfc9ec3c50] mutex_lock at ffffffffa806320c
  #6 [ffffa2bfc9ec3c68] target_free_device at ffffffffc0935998 [target_core_mod]
  #7 [ffffa2bfc9ec3c90] target_core_dev_release at ffffffffc092f975 [target_core_mod]
  #8 [ffffa2bfc9ec3ca0] config_item_put at ffffffffa79d250f
  #9 [ffffa2bfc9ec3cd0] config_item_put at ffffffffa79d2583
 #10 [ffffa2bfc9ec3ce0] target_devices_idr_iter at ffffffffc0933f3a [target_core_mod]
 #11 [ffffa2bfc9ec3d00] idr_for_each at ffffffffa803f6fc
 #12 [ffffa2bfc9ec3d60] target_for_each_device at ffffffffc0935670 [target_core_mod]
 #13 [ffffa2bfc9ec3d98] transport_deregister_session at ffffffffc0946408 [target_core_mod]
 #14 [ffffa2bfc9ec3dc8] iscsit_close_session at ffffffffc09a44a6 [iscsi_target_mod]
 #15 [ffffa2bfc9ec3df0] iscsit_close_connection at ffffffffc09a4a88 [iscsi_target_mod]
 #16 [ffffa2bfc9ec3df8] finish_task_switch at ffffffffa76e5d07
 #17 [ffffa2bfc9ec3e78] iscsit_take_action_for_connection_exit at ffffffffc0991c23 [iscsi_target_mod]
 #18 [ffffa2bfc9ec3ea0] iscsi_target_tx_thread at ffffffffc09a403b [iscsi_target_mod]
 #19 [ffffa2bfc9ec3f08] kthread at ffffffffa76d8080
 #20 [ffffa2bfc9ec3f50] ret_from_fork at ffffffffa8200364

Fixes: 36d4cb460b ("scsi: target: Avoid that EXTENDED COPY commands trigger lock inversion")
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Link: https://lore.kernel.org/r/20230918225848.66463-1-junxiao.bi@oracle.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-10-10 21:53:38 +02:00
Mike Christie
e1f59cd18a scsi: target: Fix multiple LUN_RESET handling
[ Upstream commit 673db054d7 ]

This fixes a bug where an initiator thinks a LUN_RESET has cleaned up
running commands when it hasn't. The bug was added in commit 51ec502a32
("target: Delete tmr from list before processing").

The problem occurs when:

 1. We have N I/O cmds running in the target layer spread over 2 sessions.

 2. The initiator sends a LUN_RESET for each session.

 3. session1's LUN_RESET loops over all the running commands from both
    sessions and moves them to its local drain_task_list.

 4. session2's LUN_RESET does not see the LUN_RESET from session1 because
    the commit above has it remove itself. session2 also does not see any
    commands since the other reset moved them off the state lists.

 5. sessions2's LUN_RESET will then complete with a successful response.

 6. sessions2's inititor believes the running commands on its session are
    now cleaned up due to the successful response and cleans up the running
    commands from its side. It then restarts them.

 7. The commands do eventually complete on the backend and the target
    starts to return aborted task statuses for them. The initiator will
    either throw a invalid ITT error or might accidentally lookup a new
    task if the ITT has been reallocated already.

Fix the bug by reverting the patch, and serialize the execution of
LUN_RESETs and Preempt and Aborts.

Also prevent us from waiting on LUN_RESETs in core_tmr_drain_tmr_list,
because it turns out the original patch fixed a bug that was not
mentioned. For LUN_RESET1 core_tmr_drain_tmr_list can see a second
LUN_RESET and wait on it. Then the second reset will run
core_tmr_drain_tmr_list and see the first reset and wait on it resulting in
a deadlock.

Fixes: 51ec502a32 ("target: Delete tmr from list before processing")
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Link: https://lore.kernel.org/r/20230319015620.96006-8-michael.christie@oracle.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-17 11:47:48 +02:00
Mike Christie
008b936bbd scsi: target: Make state_list per CPU
[ Upstream commit 1526d9f10c ]

Do a state_list/execute_task_lock per CPU, so we can do submissions from
different CPUs without contention with each other.

Note: tcm_fc was passing TARGET_SCF_USE_CPUID, but never set cpuid.  The
assumption is that it wanted to set the cpuid to the CPU it was submitting
from so it will get this behavior with this patch.

[mkp: s/printk/pr_err/ + resolve COMPARE AND WRITE patch conflict]

Link: https://lore.kernel.org/r/1604257174-4524-8-git-send-email-michael.christie@oracle.com
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>
Stable-dep-of: 673db054d7 ("scsi: target: Fix multiple LUN_RESET handling")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-17 11:47:48 +02:00
Christoph Hellwig
3eba802d47 target: remove an incorrect unmap zeroes data deduction
[ Upstream commit 179d8609d8 ]

For block devices, the SCSI target drivers implements UNMAP as calls to
blkdev_issue_discard, which does not guarantee zeroing just because
Write Zeroes is supported.

Note that this does not affect the file backed path which uses
fallocate to punch holes.

Fixes: 2237498f0b ("target/iblock: Convert WRITE_SAME to blkdev_issue_zeroout")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220415045258.199825-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-09 10:21:01 +02:00
Mike Christie
8176441373 scsi: target: Fix ordered tag handling
[ Upstream commit ed1227e080 ]

This patch fixes the following bugs:

1. If there are multiple ordered cmds queued and multiple simple cmds
   completing, target_restart_delayed_cmds() could be called on different
   CPUs and each instance could start a ordered cmd. They could then run in
   different orders than they were queued.

2. target_restart_delayed_cmds() and target_handle_task_attr() can race
   where:

   1. target_handle_task_attr() has passed the simple_cmds == 0 check.

   2. transport_complete_task_attr() then decrements simple_cmds to 0.

   3. transport_complete_task_attr() runs target_restart_delayed_cmds() and
      it does not see any cmds on the delayed_cmd_list.

   4. target_handle_task_attr() adds the cmd to the delayed_cmd_list.

   The cmd will then end up timing out.

3. If we are sent > 1 ordered cmds and simple_cmds == 0, we can execute
   them out of order, because target_handle_task_attr() will hit that
   simple_cmds check first and return false for all ordered cmds sent.

4. We run target_restart_delayed_cmds() after every cmd completion, so if
   there is more than 1 simple cmd running, we start executing ordered cmds
   after that first cmd instead of waiting for all of them to complete.

5. Ordered cmds are not supposed to start until HEAD OF QUEUE and all older
   cmds have completed, and not just simple.

6. It's not a bug but it doesn't make sense to take the delayed_cmd_lock
   for every cmd completion when ordered cmds are almost never used. Just
   replacing that lock with an atomic increases IOPs by up to 10% when
   completions are spread over multiple CPUs and there are multiple
   sessions/ mqs/thread accessing the same device.

This patch moves the queued delayed handling to a per device work to
serialze the cmd executions for each device and adds a new counter to track
HEAD_OF_QUEUE and SIMPLE cmds. We can then check the new counter to
determine when to run the work on the completion path.

Link: https://lore.kernel.org/r/20210930020422.92578-3-michael.christie@oracle.com
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-11-26 10:39:11 +01:00
Sudhakar Panneerselvam
a36840d800 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>
2020-06-09 21:57:26 -04:00
Lance Digby
5482d56bfe scsi: target: core: Add initiatorname to NON_EXISTENT_LUN error
The NON_EXISTENT_LUN error can be written without an error condition
on the initiator responsible. Adding the initiatorname to this message
will reduce the effort required to fix this when many initiators are
supported by a target.

This version ensures the initiator name is also printed on the same message
in transport_lookup_tmr_lun for consistency.

Link: https://lore.kernel.org/r/9b13bb2e1f52f1792cd81850ee95bf3781bb5363.1589759816.git.lance.digby@gmail.com
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Lance Digby <lance.digby@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-19 21:27:10 -04:00
Bodo Stroesser
69088a0494 scsi: target: Make transport_flags per device
pgr_support and alua_support device attributes show the inverted value of
the transport_flags:

 * TRANSPORT_FLAG_PASSTHROUGH_PGR
 * TRANSPORT_FLAG_PASSTHROUGH_ALUA

These attributes are per device, while the flags are per backend. Rename
the transport_flags in backend/transport to transport_flags_default and use
this value to initialize the new transport_flags field in the se_device
structure.

Now data and attribute both are per se_device.

Link: https://lore.kernel.org/r/20200427150823.15350-4-bstroesser@ts.fujitsu.com
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Bodo Stroesser <bstroesser@ts.fujitsu.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-05-07 22:39:21 -04:00
David Disseldorp
1bf630fddd scsi: target: use an enum to track emulate_ua_intlck_ctrl
The emulate_ua_intlck_ctrl device attribute accepts values of 0, 1 or 2 via
ConfigFS, which map to unit attention interlocks control codes in the MODE
SENSE control Mode Page.  Use an enum to track these values so that it's
clear that, unlike the remaining emulate_X attributes,
emulate_ua_intlck_ctrl isn't boolean.

Link: https://marc.info/?l=target-devel&m=158227825428798
Suggested-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: David Disseldorp <ddiss@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-02-21 17:37:16 -05:00
David Disseldorp
738981bd74 scsi: target: fix unmap_zeroes_data boolean initialisation
The LIO unmap_zeroes_data device attribute is mapped to the LBPRZ flag in
the READ CAPACITY(16) and Thin Provisioning VPD INQUIRY responses.

The unmap_zeroes_data attribute is exposed via configfs, where any write
value is correctly validated via strtobool(). However, when initialised via
target_configure_unmap_from_queue() it takes the value of the device's
max_write_zeroes_sectors queue limit, which is non-boolean.

A non-boolean value can be read from configfs, but attempting to write the
same value back results in -EINVAL, causing problems for configuration
utilities such as targetcli.

Link: https://marc.info/?l=target-devel&m=158213354011309
Fixes: 2237498f0b ("target/iblock: Convert WRITE_SAME to blkdev_issue_zeroout")
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: David Disseldorp <ddiss@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2020-02-21 17:37:13 -05:00
Bodo Stroesser
27e84243cb scsi: target: core: Do not overwrite CDB byte 1
passthrough_parse_cdb() - used by TCMU and PSCSI - attepts to reset the LUN
field of SCSI-2 CDBs (bits 5,6,7 of byte 1).  The current code is wrong as
for newer commands not having the LUN field it overwrites relevant command
bits (e.g. for SECURITY PROTOCOL IN / OUT). We think this code was
unnecessary from the beginning or at least it is no longer useful. So we
remove it entirely.

Link: https://lore.kernel.org/r/12498eab-76fd-eaad-1316-c2827badb76a@ts.fujitsu.com
Signed-off-by: Bodo Stroesser <bstroesser@ts.fujitsu.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2019-10-17 21:40:25 -04:00
Thomas Gleixner
1a59d1b8e0 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:35 -07:00
Bart Van Assche
63f7479439 scsi: target/core: Fix a race condition in the LUN lookup code
The rcu_dereference(deve->se_lun) expression occurs twice in the LUN lookup
functions. Since these expressions are not serialized against deve->se_lun
assignments each of these expressions may yield a different result. Avoid
that the wrong LUN pointer is stored in se_cmd by reading deve->se_lun only
once.

Cc: Mike Christie <mchristi@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Fixes: 29a05deebf ("target: Convert se_node_acl->device_list[] to RCU hlist") # v4.10
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2019-04-12 20:20:05 -04:00
Bart Van Assche
618baaf788 scsi: target/iscsi: Convert comments about locking into runtime checks
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>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2019-02-04 21:33:08 -05:00
David Disseldorp
3beeabd5f2 scsi: target: perform t10_wwn ID initialisation in target_alloc_device()
Initialise the t10_wwn vendor, model and revision defaults when a device is
allocated instead of when it's enabled. This ensures that custom vendor or
model strings set prior to enablement are not later overwritten with
default values.

The TRANSPORT_FLAG_PASSTHROUGH conditional can be dropped for the following
reasons:

 - target_core_pscsi overwrites the defaults in the
   pscsi_configure_device() callback.
   + the contents is then only used for ConfigFS via
     $pscsi_dev/statistics/scsi_lu/vend, etc.

 - target_core_user doesn't touch the defaults, nor are they used for
   anything outside of ConfigFS.

Signed-off-by: David Disseldorp <ddiss@suse.de>
Reviewed-by: Roman Bolshakov <r.bolshakov@yadro.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-12-07 21:54:33 -05:00
David Disseldorp
b2da4abf26 scsi: target: consistently null-terminate t10_wwn strings
In preparation for supporting user provided vendor strings, add an extra
byte to the vendor, model and revision arrays in struct t10_wwn. This
ensures that the full INQUIRY data can be carried in the arrays along with
a null-terminator.

Change a number of array readers and writers so that they account for
explicit null-termination:

- The pscsi_set_inquiry_info() and emulate_model_alias_store() codepaths
  don't currently explicitly null-terminate; fix this.

- Existing t10_wwn field dumps use for-loops which step over
  null-terminators for right-padding.
  + Use printf with width specifiers instead.

Signed-off-by: David Disseldorp <ddiss@suse.de>
Reviewed-by: Roman Bolshakov <r.bolshakov@yadro.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-12-07 21:54:33 -05:00
Bart Van Assche
db5b21a24e scsi: target/core: Use system workqueues for TMF
A quote from SAM-5: "The order in which task management requests are
processed is not specified by the SCSI architecture model.  The SCSI
architecture model does not require in-order delivery of such task
management requests or processing by the task manager in the order
received. To guarantee the processing order of task management requests
referencing sent to a specific logical unit, an application client should
not have more than one such task management request pending to that logical
unit." This means that it is safe to use the system workqueues instead of
tmr_wq for processing TMFs. An intended side effect of this patch is that
it enables concurrent processing of TMFs.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Cc: Mike Christie <mchristi@redhat.com>
Cc: David Disseldorp <ddiss@suse.de>
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-12-07 21:20:07 -05:00
Bart Van Assche
a95be3842c scsi: target/core: Simplify transport_clear_lun_ref()
Since transport_clear_lun_ref() already waits until the percpu-refcount
.release() method is called, it is not necessary to wait first until
percpu_ref_kill_and_confirm() has finished transitioning the refcount into
atomic mode. Remove the code that waits for percpu_ref_kill_and_confirm()
to complete and also the completion object that is used by that code.  This
patch does not change the behavior of the SCSI target code.

Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Cc: Mike Christie <mchristi@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Disseldorp <ddiss@suse.de>
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-12-07 21:20:07 -05:00
David Disseldorp
30c7ca9350 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>
2018-11-28 18:50:58 -05:00
David Disseldorp
b49d6f7885 scsi: target: add emulate_pr backstore attr to toggle PR support
The new emulate_pr backstore attribute allows for Persistent Reservation
and SCSI2 RESERVE/RELEASE support to be completely disabled. This can be
useful for scenarios such as:

- Ensuring ATS (Compare & Write) usage on recent VMware ESXi initiators.

- Allowing clustered (e.g. tcm-user) backends to block such requests,
  avoiding the multi-node reservation state propagation.

When explicitly disabled, PR and RESERVE/RELEASE requests receive Invalid
Command Operation Code response sense data.

Signed-off-by: David Disseldorp <ddiss@suse.de>
Reviewed-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-11-21 22:10:36 -05:00
Mike Christie
cb0f32e12c scsi: target: add helper to check if dev is configured
This just adds a helper function to check if a device is configured and it
converts the target users to use it. The next patch will add a backend
module user so those types of modules do not have to know the lio core
details.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-07-30 23:17:53 -04:00
Bart Van Assche
e936a38ac9 scsi: target: Remove se_dev_entry.ua_count
se_dev_entry.ua_count is only used to check whether or not
se_dev_entry.ua_list is empty. Use list_empty_careful() instead.  Checking
whether or not ua_list is empty without holding the lock that protects that
list is fine because the code that dequeues from that list will check again
whether or not that list is empty.

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Mike Christie <mchristi@redhat.com>
Cc: Mike Christie <mchristi@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-07-02 16:44:32 -04:00
Bart Van Assche
36d4cb460b scsi: target: Avoid that EXTENDED COPY commands trigger lock inversion
The approach for adding a device to the devices_idr data structure and for
removing it is as follows:

* &dev->dev_group.cg_item is initialized before a device is added to
  devices_idr.

* If the reference count of a device drops to zero then
  target_free_device() removes the device from devices_idr.

* All devices_idr manipulations are protected by device_mutex.

This means that increasing the reference count of a device is sufficient to
prevent removal from devices_idr and also that it is safe access
dev_group.cg_item for any device that is referenced by devices_idr. Use
this to modify target_find_device() and target_for_each_device() such that
these functions no longer introduce a dependency between device_mutex and
the configfs root inode mutex.

Note: it is safe to pass a NULL pointer to config_item_put() and also to
config_item_get_unless_zero().

This patch prevents that lockdep reports the following complaint:

======================================================
WARNING: possible circular locking dependency detected
4.12.0-rc1-dbg+ #1 Not tainted
------------------------------------------------------
rmdir/12053 is trying to acquire lock:
 (device_mutex#2){+.+.+.}, at: [<ffffffffa010afce>]
target_free_device+0xae/0xf0 [target_core_mod]

but task is already holding lock:
 (&sb->s_type->i_mutex_key#14){++++++}, at: [<ffffffff811c5c30>]
vfs_rmdir+0x50/0x140

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (&sb->s_type->i_mutex_key#14){++++++}:
       lock_acquire+0x59/0x80
       down_write+0x36/0x70
       configfs_depend_item+0x3a/0xb0 [configfs]
       target_depend_item+0x13/0x20 [target_core_mod]
       target_xcopy_locate_se_dev_e4_iter+0x87/0x100 [target_core_mod]
       target_devices_idr_iter+0x16/0x20 [target_core_mod]
       idr_for_each+0x39/0xc0
       target_for_each_device+0x36/0x50 [target_core_mod]
       target_xcopy_locate_se_dev_e4+0x28/0x80 [target_core_mod]
       target_xcopy_do_work+0x2e9/0xdd0 [target_core_mod]
       process_one_work+0x1ca/0x3f0
       worker_thread+0x49/0x3b0
       kthread+0x109/0x140
       ret_from_fork+0x31/0x40

-> #0 (device_mutex#2){+.+.+.}:
       __lock_acquire+0x101f/0x11d0
       lock_acquire+0x59/0x80
       __mutex_lock+0x7e/0x950
       mutex_lock_nested+0x16/0x20
       target_free_device+0xae/0xf0 [target_core_mod]
       target_core_dev_release+0x10/0x20 [target_core_mod]
       config_item_put+0x6e/0xb0 [configfs]
       configfs_rmdir+0x1a6/0x300 [configfs]
       vfs_rmdir+0xb7/0x140
       do_rmdir+0x1f4/0x200
       SyS_rmdir+0x11/0x20
       entry_SYSCALL_64_fastpath+0x23/0xc2

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&sb->s_type->i_mutex_key#14);
                               lock(device_mutex#2);
                               lock(&sb->s_type->i_mutex_key#14);
  lock(device_mutex#2);

 *** DEADLOCK ***

3 locks held by rmdir/12053:
 #0:  (sb_writers#10){.+.+.+}, at: [<ffffffff811e223f>]
mnt_want_write+0x1f/0x50
 #1:  (&sb->s_type->i_mutex_key#14/1){+.+.+.}, at: [<ffffffff811cb97e>]
do_rmdir+0x15e/0x200
 #2:  (&sb->s_type->i_mutex_key#14){++++++}, at: [<ffffffff811c5c30>]
vfs_rmdir+0x50/0x140

stack backtrace:
CPU: 3 PID: 12053 Comm: rmdir Not tainted 4.12.0-rc1-dbg+ #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.0.0-prebuilt.qemu-project.org 04/01/2014
Call Trace:
 dump_stack+0x86/0xcf
 print_circular_bug+0x1c7/0x220
 __lock_acquire+0x101f/0x11d0
 lock_acquire+0x59/0x80
 __mutex_lock+0x7e/0x950
 mutex_lock_nested+0x16/0x20
 target_free_device+0xae/0xf0 [target_core_mod]
 target_core_dev_release+0x10/0x20 [target_core_mod]
 config_item_put+0x6e/0xb0 [configfs]
 configfs_rmdir+0x1a6/0x300 [configfs]
 vfs_rmdir+0xb7/0x140
 do_rmdir+0x1f4/0x200
 SyS_rmdir+0x11/0x20
 entry_SYSCALL_64_fastpath+0x23/0xc2

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
[Rebased to handle conflict withe target_find_device removal]
Signed-off-by: Mike Christie <mchristi@redhat.com>

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-07-02 16:44:30 -04:00
Mike Christie
e260748437 scsi: target: remove target_find_device
target_find_device is no longer used, so remove it.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Tested-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-06-26 12:27:06 -04:00
tangwenji
c82b59e7c3 target: fix destroy device in target_configure_device
After dev->transport->configure_device succeeds, target_configure_device
exits abnormally, dev_flags has not set DF_CONFIGURED yet, does not call
destroy_device function in free_device.

Signed-off-by: tangwenji <tang.wenji@zte.com.cn>
Acked-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2018-01-18 01:21:11 -08:00
Tang Wenji
388fe6996b target: Fix cmd size for PR-OUT in passthrough_parse_cdb
The cmd size should be 4bytes form byte5 to byte8 when CDB opcode
is PERSISTENT_RESERVE_OUT in SPC3 and SPC4

(Also fix up the same in spc_parse_cdb - MNC)

Signed-off-by: Tang Wenji <tang.wenji@zte.com.cn>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2017-07-09 20:58:49 -07:00
Damien Le Moal
e5dc9a7055 target: Use macro for WRITE_VERIFY_32 operation codes
Add WRITE_VERIFY_32 definition to scsi prototypes and use this macro
definition isntead of the hard coded value.

(Drop WRITE_VERIFY_16 that's already part of another patch - nab)

Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2017-07-06 23:11:49 -07:00
Colin Ian King
c82ff239ec target: make device_mutex and device_list static
Variables device_mutex and device_list static are local to the source,
so make them static.

Cleans up sparse warnings:
"symbol 'device_list' was not declared. Should it be static?"
"symbol 'device_mutex' was not declared. Should it be static?"

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2017-07-06 23:11:44 -07:00
Mike Christie
be50f538e9 target: remove g_device_list
g_device_list is no longer needed because we now use the idr code
for lookups and seaches.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2017-07-06 23:11:41 -07:00
Mike Christie
b1943fd454 target: add helper to iterate over devices
This adds a wrapper around idr_for_each so the xcopy code can loop over
the devices in the next patch.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2017-07-06 23:11:39 -07:00
Mike Christie
85441e6b8c target: add helper to find se_device by dev_index
This adds a helper to find a se_device by dev_index. It will
be used in the next patches so tcmu's netlink interface can
execute commands on specific devices.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2017-07-06 23:11:38 -07:00
Mike Christie
0a5eee647b target: use idr for se_device dev index
In the next patches we will add tcmu netlink support that allows
userspace to send commands to target_core_user. To execute operations
on a se_device/tcmu_dev we need to be able to look up a dev by any old
id. This patch replaces the se_device->dev_index with a idr created
id.

The next patches will also remove the g_device_list and replace it with
the idr.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2017-07-06 23:11:37 -07:00
Mike Christie
926347061e target: break up free_device callback
With this patch free_device is now used to free what is allocated in the
alloc_device callback and destroy_device tears down the resources that are
setup in the configure_device callback.

This patch will be needed in the next patch where tcmu needs
to be able to look up the device in the destroy callback.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2017-07-06 23:11:37 -07:00
Bart Van Assche
a85d667e58 target: Use {get,put}_unaligned_be*() instead of open coding these functions
Introduce the function get_unaligned_be24(). Use {get,put}_unaligned_be*()
where appropriate. This patch does not change any functionality.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Cc: Andy Grover <agrover@redhat.com>
Cc: David Disseldorp <ddiss@suse.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2017-07-06 22:57:59 -07:00
Bart Van Assche
9f2f342892 target: Remove se_device.dev_list
The last user of se_device.dev_list was removed through commit
0fd97ccf45 ("target: kill struct se_subsystem_dev"). Hence
also remove se_device.dev_list.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Andy Grover <agrover@redhat.com>
Cc: David Disseldorp <ddiss@suse.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2017-07-06 22:57:58 -07:00
Bart Van Assche
3e182db787 target: Use symbolic value for WRITE_VERIFY_16
Now that a symbolic value has been introduced for WRITE_VERIFY_16,
use it. This patch does not change any functionality.

References: commit c2d26f18dc ("target: Add WRITE_VERIFY_16")
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Bryant G. Ly <bryantly@linux.vnet.ibm.com>
Cc: Andy Grover <agrover@redhat.com>
Cc: David Disseldorp <ddiss@suse.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2017-07-06 22:57:57 -07:00
Nicholas Bellinger
eeb64d239e target: Add support for TMR percpu reference counting
This patch introduces TMR percpu reference counting using
se_lun->lun_ref in transport_lookup_tmr_lun(), following
how existing non TMR per se_lun reference counting works
within transport_lookup_cmd_lun().

It also adds explicit transport_lun_remove_cmd() calls to
drop the reference in the three tmr related locations that
invoke transport_cmd_check_stop_to_fabric();

   - target_tmr_work() during normal ->queue_tm_rsp()
   - target_complete_tmr_failure() during error ->queue_tm_rsp()
   - transport_generic_handle_tmr() during early failure

Also, note the exception paths in transport_generic_free_cmd()
and transport_cmd_finish_abort() already check SCF_SE_LUN_CMD,
and will invoke transport_lun_remove_cmd() when necessary.

Reviewed-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Reviewed-by: Quinn Tran <quinn.tran@cavium.com>
Cc: Mike Christie <mchristi@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2017-07-06 22:57:55 -07:00
Nicholas Bellinger
c17cd24959 target/configfs: Kill se_device->dev_link_magic
Instead of using a hardcoded magic value in se_device when verifying
a target config_item symlink source during target_fabric_port_link(),
go ahead and use target_core_dev_item_ops directly instead.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Mike Christie <mchristi@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2017-06-08 23:26:38 -07:00
Nicholas Bellinger
2237498f0b target/iblock: Convert WRITE_SAME to blkdev_issue_zeroout
The people who are actively using iblock_execute_write_same_direct() are
doing so in the context of ESX VAAI BlockZero, together with
EXTENDED_COPY and COMPARE_AND_WRITE primitives.

In practice though I've not seen any users of IBLOCK WRITE_SAME for
anything other than VAAI BlockZero, so just using blkdev_issue_zeroout()
when available, and falling back to iblock_execute_write_same() if the
WRITE_SAME buffer contains anything other than zeros should be OK.

(Hook up max_write_zeroes_sectors to signal LBPRZ feature bit in
 target_configure_unmap_from_queue - nab)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Mike Christie <mchristi@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Jens Axboe <axboe@fb.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2017-06-08 23:26:37 -07:00
Linus Torvalds
bd1286f964 Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
Pull SCSI target updates from Nicholas Bellinger:
 "Things were a lot more calm than previously expected. It's primarily
  fixes in various areas, with most of the new functionality centering
  around TCMU backend driver work that Xiubo Li has been driving.

  Here's the summary on the feature side:

   - Make T10-PI verify configurable for emulated (FILEIO + RD) backends
    (Dmitry Monakhov)
   - Allow target-core/TCMU pass-through to use in-kernel SPC-PR logic
    (Bryant Ly + MNC)
   - Add TCMU support for growing ring buffer size (Xiubo Li + MNC)
   - Add TCMU support for global block data pool (Xiubo Li + MNC)

  and on the bug-fix side:

   - Fix COMPARE_AND_WRITE non GOOD status handling for READ phase
    failures (Gary Guo + nab)
   - Fix iscsi-target hang with explicitly changing per NodeACL
    CmdSN number depth with concurrent login driven session
    reinstatement.  (Gary Guo + nab)
   - Fix ibmvscsis fabric driver ABORT task handling (Bryant Ly)
   - Fix target-core/FILEIO zero length handling (Bart Van Assche)

  Also, there was an OOPs introduced with the WRITE_VERIFY changes that
  I ended up reverting at the last minute, because as not unusual Bart
  and I could not agree on the fix in time for -rc1. Since it's specific
  to a conformance test, it's been reverted for now.

  There is a separate patch in the queue to address the underlying
  control CDB write overflow regression in >= v4.3 separate from the
  WRITE_VERIFY revert here, that will be pushed post -rc1"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (30 commits)
  Revert "target: Fix VERIFY and WRITE VERIFY command parsing"
  IB/srpt: Avoid that aborting a command triggers a kernel warning
  IB/srpt: Fix abort handling
  target/fileio: Fix zero-length READ and WRITE handling
  ibmvscsis: Do not send aborted task response
  tcmu: fix module removal due to stuck thread
  target: Don't force session reset if queue_depth does not change
  iscsi-target: Set session_fall_back_to_erl0 when forcing reinstatement
  target: Fix compare_and_write_callback handling for non GOOD status
  tcmu: Recalculate the tcmu_cmd size to save cmd area memories
  tcmu: Add global data block pool support
  tcmu: Add dynamic growing data area feature support
  target: fixup error message in target_tg_pt_gp_tg_pt_gp_id_store()
  target: fixup error message in target_tg_pt_gp_alua_access_type_store()
  target/user: PGR Support
  target: Add WRITE_VERIFY_16
  Documentation/target: add an example script to configure an iSCSI target
  target: Use kmalloc_array() in transport_kmap_data_sg()
  target: Use kmalloc_array() in compare_and_write_callback()
  target: Improve size determinations in two functions
  ...
2017-05-12 11:44:13 -07:00
Bryant G. Ly
4ec5bf0ea8 target/user: PGR Support
This adds initial PGR support for just TCMU, since tcmu doesn't
have the necessary IT_NEXUS info to process PGR in userspace,
so have those commands be processed in kernel.

HA support is not available yet, we will work on it if this patch
is acceptable.

Signed-off-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2017-05-01 22:21:45 -07:00
Christoph Hellwig
48920ff2a5 block: remove the discard_zeroes_data flag
Now that we use the proper REQ_OP_WRITE_ZEROES operation everywhere we can
kill this hack.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-08 11:25:38 -06:00
Nicholas Bellinger
bd4e2d2907 target: Fix NULL dereference during LUN lookup + active I/O shutdown
When transport_clear_lun_ref() is shutting down a se_lun via
configfs with new I/O in-flight, it's possible to trigger a
NULL pointer dereference in transport_lookup_cmd_lun() due
to the fact percpu_ref_get() doesn't do any __PERCPU_REF_DEAD
checking before incrementing lun->lun_ref.count after
lun->lun_ref has switched to atomic_t mode.

This results in a NULL pointer dereference as LUN shutdown
code in core_tpg_remove_lun() continues running after the
existing ->release() -> core_tpg_lun_ref_release() callback
completes, and clears the RCU protected se_lun->lun_se_dev
pointer.

During the OOPs, the state of lun->lun_ref in the process
which triggered the NULL pointer dereference looks like
the following on v4.1.y stable code:

struct se_lun {
  lun_link_magic = 4294932337,
  lun_status = TRANSPORT_LUN_STATUS_FREE,

  .....

  lun_se_dev = 0x0,
  lun_sep = 0x0,

  .....

  lun_ref = {
    count = {
      counter = 1
    },
    percpu_count_ptr = 3,
    release = 0xffffffffa02fa1e0 <core_tpg_lun_ref_release>,
    confirm_switch = 0x0,
    force_atomic = false,
    rcu = {
      next = 0xffff88154fa1a5d0,
      func = 0xffffffff8137c4c0 <percpu_ref_switch_to_atomic_rcu>
    }
  }
}

To address this bug, use percpu_ref_tryget_live() to ensure
once __PERCPU_REF_DEAD is visable on all CPUs and ->lun_ref
has switched to atomic_t, all new I/Os will fail to obtain
a new lun->lun_ref reference.

Also use an explicit percpu_ref_kill_and_confirm() callback
to block on ->lun_ref_comp to allow the first stage and
associated RCU grace period to complete, and then block on
->lun_ref_shutdown waiting for the final percpu_ref_put()
to drop the last reference via transport_lun_remove_cmd()
before continuing with core_tpg_remove_lun() shutdown.

Reported-by: Rob Millner <rlm@daterainc.com>
Tested-by: Rob Millner <rlm@daterainc.com>
Cc: Rob Millner <rlm@daterainc.com>
Tested-by: Vaibhav Tandon <vst@datera.io>
Cc: Vaibhav Tandon <vst@datera.io>
Tested-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org> # v3.14+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2017-02-26 16:08:44 -08:00
Bart Van Assche
4f4c6c3ddb target: Remove se_tmr_req.tmr_lun
Member tmr_lun of se_tmr_req is set but not used. Hence remove it.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Cc: Giridhar Malavali <giridhar.malavali@cavium.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2017-02-09 00:39:10 -08:00
Nicholas Bellinger
391e2a6de9 target: Don't BUG_ON during NodeACL dynamic -> explicit conversion
After the v4.2+ RCU conversion to se_node_acl->lun_entry_hlist,
a BUG_ON() was added in core_enable_device_list_for_node() to
detect when the located orig->se_lun_acl contains an existing
se_lun_acl pointer reference.

However, this scenario can happen when a dynamically generated
NodeACL is being converted to an explicit NodeACL, when the
explicit NodeACL contains a different LUN mapping than the
default provided by the WWN endpoint.

So instead of triggering BUG_ON(), go ahead and fail instead
following the original pre RCU conversion logic.

Reported-by: Benjamin ESTRABAUD <ben.estrabaud@mpstor.com>
Cc: Benjamin ESTRABAUD <ben.estrabaud@mpstor.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org # 4.2+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2017-02-08 07:46:31 -08:00
Bart Van Assche
8dcf07be2d 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>
2016-12-09 10:22:28 -08:00
Mike Christie
ea263c7fad target: Fix max_unmap_lba_count calc overflow
max_discard_sectors only 32bits, and some non scsi backend
devices will set this to the max 0xffffffff, so we can end up
overflowing during the max_unmap_lba_count calculation.

This fixes a regression caused by my patch:

commit 8a9ebe717a
Author: Mike Christie <mchristi@redhat.com>
Date:   Mon Jan 18 14:09:27 2016 -0600

    target: Fix WRITE_SAME/DISCARD conversion to linux 512b sectors

which can result in extra discards being sent to due the overflow
causing max_unmap_lba_count to be smaller than what the backing
device can actually support.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: stable@vger.kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2016-07-20 00:58:36 -07:00
Andy Grover
03a68b44fa target: Remove enum transport_lunflags_table
se_dev_entry.lun_flags and se_lun.lun_access are only used for keeping
track of read-write vs. read-only state. Since this is an either/or thing
we can represent it as bool, and remove the unneeded enum
transport_lunflags_table, which is left over from when there were more
flags.

Change code that uses this enum to just use true/false, and make it clear
through variable and param names that true means read-only, false means
read-write.

Signed-off-by: Andy Grover <agrover@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2016-03-10 21:48:55 -08:00
Mike Christie
8a9ebe717a target: Fix WRITE_SAME/DISCARD conversion to linux 512b sectors
In a couple places we are not converting to/from the Linux
block layer 512 bytes sectors.

1.

The request queue values and what we do are a mismatch of
things:

max_discard_sectors - This is in linux block layer 512 byte
sectors. We are just copying this to max_unmap_lba_count.

discard_granularity - This is in bytes. We are converting it
to Linux block layer 512 byte sectors.

discard_alignment - This is in bytes. We are just copying
this over.

The problem is that the core LIO code exports these values in
spc_emulate_evpd_b0 and we use them to test request arguments
in sbc_execute_unmap, but we never convert to the block size
we export to the initiator. If we are not using 512 byte sectors
then we are exporting the wrong values or are checks are off.
And, for the discard_alignment/bytes case we are just plain messed
up.

2.

blkdev_issue_discard's start and number of sector arguments
are supposed to be in linux block layer 512 byte sectors. We are
currently passing in the values we get from the initiator which
might be based on some other sector size.

There is a similar problem in iblock_execute_write_same where
the bio functions want values in 512 byte sectors but we are
passing in what we got from the initiator.

Signed-off-by: Mike Christie <mchristi@redhat.com>
Cc: stable@vger.kernel.org # 3.10+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2016-01-29 19:29:34 -08:00