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181 Commits (27e84243cb63601a10e366afe3e2d05bb03c1cb5)

Author SHA1 Message Date
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
Jamie Pocas e6f41633cb target/sbc: Add LBPRZ attribute + control CDB emulation
This change sets the LBPRZ flag in EVPD page b2h and READ CAPACITY (16)
based on a new unmap_zeroes_data device attribute. This flag is set
automatically for iblock based on underlying block device queue's
discard_zeroes_data flag.

Signed-off-by: Jamie Pocas <jamie.pocas@emc.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2016-01-06 13:39:55 -08:00
Nicholas Bellinger 8fa3a86748 target: Make TCM_WRITE_PROTECT failure honor D_SENSE bit
This patch changes transport_lookup_cmd_lun() to obtain
se_lun->lun_ref + se_cmd->se_device rcu_dereference during
TCM_WRITE_PROTECT -> CHECK_CONDITION failure status.

Do this to ensure the active control D_SENSE mode page bit
is being honored.

Reported-by: Sagi Grimberg <sagig@mellanox.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2015-09-24 23:17:27 -07:00
Nicholas Bellinger 3ccd6e83df target: Fix PR registration + APTPL RCU conversion regression
This patch fixes a v4.2+ regression introduced by commit 79dc9c9e86
where lookup of t10_pr_registration->pr_reg_deve and associated
->pr_kref get was missing from __core_scsi3_do_alloc_registration(),
which is responsible for setting DEF_PR_REG_ACTIVE.

This would result in REGISTER operations completing successfully,
but subsequent core_scsi3_pr_seq_non_holder() checking would fail
with !DEF_PR_REG_ACTIVE -> RESERVATION CONFLICT status.

Update __core_scsi3_add_registration() to drop ->pr_kref reference
after registration and any optional ALL_TG_PT=1 processing has
completed.  Update core_scsi3_decode_spec_i_port() to release
the new parent local_pr_reg->pr_kref as well.

Also, update __core_scsi3_check_aptpl_registration() to perform
the same target_nacl_find_deve() lookup + ->pr_kref get, now that
__core_scsi3_add_registration() expects to drop the reference.

Finally, since there are cases when se_dev_entry->se_lun_acl can
still be dereferenced in core_scsi3_lunacl_undepend_item() while
holding ->pr_kref, go ahead and move explicit rcu_assign_pointer()
NULL assignments within core_disable_device_list_for_node() until
after orig->pr_comp finishes.

Reported-by: Scott L. Lykens <scott@lykens.org>
Tested-by: Scott L. Lykens <scott@lykens.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Lee Duncan <lduncan@suse.com>
Cc: <stable@vger.kernel.org> # v4.2+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2015-09-24 23:17:07 -07:00
Roland Dreier 9c31820b6a target: Remove cmd->se_ordered_id (unused except debug log lines)
For every command, we set se_ordered_id by doing atomic_inc_return on
dev->dev_ordered_id for the corresponding device.  However, the only
places this value gets used are in pr_debug() calls, which doesn't
seem worth an extra atomic op per IO.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2015-07-31 00:06:12 -07:00
Chris Zankel b6a54b8d89 target: remove initiatorname field in se_acl_lun
From: Chris Zankel <czankel@purestorage.com>

The initiatorname field in se_acl_lun is only a copy of the same field
in se_node_acl, so remove it and use the version in se_node_acl where
needed (it's actually only used for pr_debug)

Signed-off-by: Chris Zankel <czankel@purestorage.com>
Signed-off-by: Spencer Baugh <spencer.baugh@purestorage.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2015-07-30 22:57:30 -07:00
Sagi Grimberg fe052a1810 target: Use struct t10_pi_tuple
Its not a good idea to keep target specific definition of
the same t10-pi tuple.

(Fix v4.2-rc1 patch fuzz - nab)

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2015-07-06 14:31:50 -07:00
Linus Torvalds 5c755fe142 Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
Pull SCSI target updates from Nicholas Bellinger:
 "It's been a busy development cycle for target-core in a number of
  different areas.

  The fabric API usage for se_node_acl allocation is now within
  target-core code, dropping the external API callers for all fabric
  drivers tree-wide.

  There is a new conversion to RCU hlists for se_node_acl and
  se_portal_group LUN mappings, that turns fast-past LUN lookup into a
  completely lockless code-path.  It also removes the original
  hard-coded limitation of 256 LUNs per fabric endpoint.

  The configfs attributes for backends can now be shared between core
  and driver code, allowing existing drivers to use common code while
  still allowing flexibility for new backend provided attributes.

  The highlights include:

   - Merge sbc_verify_dif_* into common code (sagi)
   - Remove iscsi-target support for obsolete IFMarker/OFMarker
     (Christophe Vu-Brugier)
   - Add bidi support in target/user backend (ilias + vangelis + agover)
   - Move se_node_acl allocation into target-core code (hch)
   - Add crc_t10dif_update common helper (akinobu + mkp)
   - Handle target-core odd SGL mapping for data transfer memory
     (akinobu)
   - Move transport ID handling into target-core (hch)
   - Move task tag into struct se_cmd + support 64-bit tags (bart)
   - Convert se_node_acl->device_list[] to RCU hlist (nab + hch +
     paulmck)
   - Convert se_portal_group->tpg_lun_list[] to RCU hlist (nab + hch +
     paulmck)
   - Simplify target backend driver registration (hch)
   - Consolidate + simplify target backend attribute implementations
     (hch + nab)
   - Subsume se_port + t10_alua_tg_pt_gp_member into se_lun (hch)
   - Drop lun_sep_lock for se_lun->lun_se_dev RCU usage (hch + nab)
   - Drop unnecessary core_tpg_register TFO parameter (nab)
   - Use 64-bit LUNs tree-wide (hannes)
   - Drop left-over TARGET_MAX_LUNS_PER_TRANSPORT limit (hannes)"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (76 commits)
  target: Bump core version to v5.0
  target: remove target_core_configfs.h
  target: remove unused TARGET_CORE_CONFIG_ROOT define
  target: consolidate version defines
  target: implement WRITE_SAME with UNMAP bit using ->execute_unmap
  target: simplify UNMAP handling
  target: replace se_cmd->execute_rw with a protocol_data field
  target/user: Fix inconsistent kmap_atomic/kunmap_atomic
  target: Send UA when changing LUN inventory
  target: Send UA upon LUN RESET tmr completion
  target: Send UA on ALUA target port group change
  target: Convert se_lun->lun_deve_lock to normal spinlock
  target: use 'se_dev_entry' when allocating UAs
  target: Remove 'ua_nacl' pointer from se_ua structure
  target_core_alua: Correct UA handling when switching states
  xen-scsiback: Fix compile warning for 64-bit LUN
  target: Remove TARGET_MAX_LUNS_PER_TRANSPORT
  target: use 64-bit LUNs
  target: Drop duplicate + unused se_dev_check_wce
  target: Drop unnecessary core_tpg_register TFO parameter
  ...
2015-07-04 14:13:43 -07:00
Linus Torvalds acd53127c4 SCSI misc on 20150622
This is the usual grab bag of driver updates (lpfc, hpsa,
 megaraid_sas, cxgbi, be2iscsi) plus an assortment of minor updates.
 There are also one new driver: the Cisco snic; the advansys driver has
 been rewritten to get rid of the warning about converting it to the
 DMA API, the tape statistics patch got in and finally, there's a
 resuffle of SCSI header files to separate more cleanly initiator from
 target mode (and better share the common definitions).
 
 Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI updates from James Bottomley:
 "This is the usual grab bag of driver updates (lpfc, hpsa,
  megaraid_sas, cxgbi, be2iscsi) plus an assortment of minor updates.

  There is also one new driver: the Cisco snic.  The advansys driver has
  been rewritten to get rid of the warning about converting it to the
  DMA API, the tape statistics patch got in and finally, there's a
  resuffle of SCSI header files to separate more cleanly initiator from
  target mode (and better share the common definitions)"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (156 commits)
  snic: driver for Cisco SCSI HBA
  qla2xxx: Fix indentation
  qla2xxx: Comment out unreachable code
  fusion: remove dead MTRR code
  advansys: fix compilation errors and warnings when CONFIG_PCI is not set
  mptsas: fix depth param in scsi_track_queue_full
  megaraid: fix irq setup process regression
  lpfc: Update version to 10.7.0.0 for upstream patch set.
  lpfc: Fix to drop PLOGIs from fabric node till LOGO processing completes
  lpfc: Fix scsi task management error message.
  lpfc: Fix cq_id masking problem.
  lpfc: Fix scsi prep dma buf error.
  lpfc: Add support for using block multi-queue
  lpfc: Devices are not discovered during takeaway/giveback testing
  lpfc: Fix vport deletion failure.
  lpfc: Check for active portpeerbeacon.
  lpfc: Update driver version for upstream patch set 10.6.0.1.
  lpfc: Change buffer pool empty message to miscellaneous category
  lpfc: Fix incorrect log message reported for empty FCF record.
  lpfc: Fix rport leak.
  ...
2015-06-23 15:55:44 -07:00
Hannes Reinecke 7c0d0d51d2 target: Send UA when changing LUN inventory
When changind the LUN inventory via core_enable_device_list_for_node()
or core_disable_device_list_for_node() a REPORTED LUNS DATA HAS CHANGED
UA should be send.

(Convert to target_luns_data_has_changed helper usage - hch)

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2015-06-23 00:43:02 -07:00
Nicholas Bellinger 1adff1b3a7 target: Convert se_lun->lun_deve_lock to normal spinlock
This patch converts se_lun->lun_deve_lock acquire/release access
to use a normal, non bottom-half spin_lock_t for protecting
se_lun->lun_deve_list access.

Reported-by: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2015-06-22 23:54:10 -07:00
Hannes Reinecke 196e2e2aa3 target: Remove TARGET_MAX_LUNS_PER_TRANSPORT
LUN allocation is now fully dynamic, so there is no need to
artificially restrain the number of exported LUNs.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2015-06-15 23:26:03 -07:00