Remove the ScsiResult macro and open code it on all call sites.

This will make subsequent refactoring in this area easier.
Signed-off-by: NJohannes Thumshirn <jthumshirn@suse.de>
Cc: James Smart <james.smart@broadcom.com>
Cc: Dick Kennedy <dick.kennedy@broadcom.com>
Reviewed-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Remove the ScsiResult macro and open code it on all call sites.

This will make subsequent refactoring in this area easier.
Signed-off-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Remove the AAC_STAT_GOOD definition and open code it in the places it was
used.

This will make subsequent refactoring in this area easier.
Signed-off-by: NJohannes Thumshirn <jthumshirn@suse.de>
Cc: Dave Carroll <david.carroll@microsemi.com>
Cc: Raghava Aditya Renukunta <RaghavaAditya.Renukunta@microsemi.com>
Reviewed-by: NDave Carroll <david.carroll@microsemi.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

fc_rport_login() will be calling mutex_lock() while running inside an
RCU-protected section, triggering the warning 'sleeping function called
from invalid context'.  To fix this we can drop the rcu functions here
altogether as the disc mutex protecting the list itself is already held,
preventing any list manipulation.

Fixes: a407c593 ("scsi: libfc: Fixup disc_mutex handling")
Signed-off-by: NHannes Reinecke <hare@suse.com>
Acked-by: NJohannes Thumshirn <jth@kernel.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Convert the free text locking notes into proper lockdep annotations.
Signed-off-by: NHannes Reinecke <hare@suse.com>
Acked-by: NJohannes Thumshirn <jth@kernel.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

It has been more than one year since we tried to change the default from
legacy to multi queue in SCSI with commit c279bd9e406 ("scsi: default to
scsi-mq"). But due to issues with suspend/resume and performance problems
it had been reverted again with commit cbe7dfa2 ("Revert "scsi: default
to scsi-mq"").

In the meantime there have been a substantial amount of performance
improvements and suspend/resume got fixed as well, thus we can re-enable
scsi-mq without a significant performance penalty.
Signed-off-by: NJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Reviewed-by: NMing Lei <ming.lei@redhat.com>
Acked-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

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

Warning level 2 was used: -Wimplicit-fallthrough=2
Signed-off-by: NGustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The target core runs into a warning in the linux/sbitmap.h
file in some configurations:

In file included from include/target/target_core_base.h:7,
                 from drivers/target/target_core_fabric_lib.c:41:
include/linux/sbitmap.h:331:46: error: 'struct seq_file' declared inside parameter list will not be visible outside of this definition or declaration [-Werror]
 void sbitmap_show(struct sbitmap *sb, struct seq_file *m);
                                              ^~~~~~~~

In general, headers should not depend on others being included first,
so this fixes it with a forward declaration for that struct name, but
we probably want to merge the patch through the scsi tree to help
bisection.

Fixes: 10e9cbb6 ("scsi: target: Convert target drivers to use sbitmap")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Reviewed-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NOmar Sandoval <osandov@fb.com>
Reviewed-by: NJens Axboe <axboe@kernel.dk>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Change references from "Broadcom Limited" to "Broadcom Inc." in the
copyright message. Update copyright duration if not yet updated for 2018.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Update the driver version to 12.0.0.5
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

A race condition between the context of devloss timeout handler and I/O
completion caused devloss timeout handler de-referencing pointer that had
been released.

Added the check in lpfc_sli_validate_fcp_iocb() on LPFC_IO_ON_TXCMPLQ to
capture the race condition of I/O completion and devloss timeout handler
attemption for aborting the I/O. Also, added check on lpfc_cmd->rdata
pointer before de-referenceing lpfc_cmd->rdata->pnode.

Also, added protection in lpfc_sli_abort_iocb() routine on driver performed
FCP I/O FLUSHING already under way before proceeding to aborting I/Os.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Kernel occasionally crashed with the following
ops on NVME Target:
  BUG: unable to handle kernel NULL pointer dereference at 0000000000000058
  IP: [<ffffffffa042ee50>] lpfc_nvmet_defer_rcv+0x50/0x70 [lpfc]

Callback routine was called for deferred rcv when it should be treated as a
normal rcv.

Added code in callback routine to detect this condition and log a message,
then bail.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Current implementation missed setting the duration field. Correct the code
to set the field.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The PBDE optimizations aren't supported in all firmware revs.

Make optimizations configurable in case there's a side effect on old
firmware.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

rmmod of driver hangs

As driver instances were being unloaded, the NVME target port was unloaded
first. During the unload, the NVME initiator port sent a heartbeat
IO. Because of the target port state, that IO was scheduled for an Abort;
however, that abort subsequently failed. The failure was not cleaned up
properly and lpfc_sli4_xri_exchange_busy_wait silently hung forever.

Clean failed abort properly and make lpfc_sli4_xri_exchange_busy_wait not
hangs silently while waiting for aborts to complete.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

System crashes when the lpfc module is unloaded after making the port
offline

The nvme queue pointers were freed during port offline, but were later
accessed in pci remove path.

Validate the pointers in pci remove path before accessing them.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Driver is incorrectly formatting a register on new hardware, using a format
for an older chip. This can result in non-deterministic behavior.

Ensure driver is not setting "workqueue index" in the WQ doorbell when
making a non-dpp doorbell write. The field must be zero when non-dpp.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Kernel crashes during fill_read_buffer when nvme_info sysfs file read.

With multiple NVME targets, approx 40, nvme_info may grow larger than
PAGE_SIZE bytes.  snprintf(buf + len, PAGE_SIZE - len, ...) logic is flawed
as PAGE_SIZE - len can be < 0 and is accepted by snprintf.  This results in
buffer overflow, and is detected with check from dev_attr_show and
fill_read_buffer.

Change to use scnprintf to a tmp array, before calling strlcat to ensure no
buffer overflow over PAGE_SIZE bytes.

Message "6314" created as a new message indicating when there is more nvme
info, but is truncated to fit within PAGE_SIZE bytes.
Signed-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <james.smart@broadcom.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

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: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NMike 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: NMartin K. Petersen <martin.petersen@oracle.com>

Send a valid ASC / ASCQ combination back to the initiator if a SCSI command
is received after a LUN has been removed. This patch fixes the following
call trace:

WARNING: CPU: 0 PID: 4 at drivers/target/target_core_transport.c:3131 translate_sense_reason+0x164/0x190 [target_core_mod]
Workqueue: ib-comp-wq ib_cq_poll_work [ib_core]
RIP: 0010:translate_sense_reason+0x164/0x190 [target_core_mod]
Call Trace:
transport_send_check_condition_and_sense+0x95/0x1c0 [target_core_mod]
transport_generic_request_failure+0x102/0x270 [target_core_mod]
transport_generic_new_cmd+0x138/0x340 [target_core_mod]
transport_handle_cdb_direct+0x2f/0x80 [target_core_mod]
target_submit_cmd_map_sgls+0x212/0x2a0 [target_core_mod]
srpt_handle_new_iu+0x244/0x680 [ib_srpt]
__ib_process_cq+0x6d/0xc0 [ib_core]
ib_cq_poll_work+0x18/0x50 [ib_core]
process_one_work+0x20b/0x6a0
worker_thread+0x35/0x380
kthread+0x117/0x130
ret_from_fork+0x24/0x30
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NMike 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: NMartin K. Petersen <martin.petersen@oracle.com>

Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NMike 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: NMartin K. Petersen <martin.petersen@oracle.com>

This patch does not change any functionality.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NMike 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: NMartin K. Petersen <martin.petersen@oracle.com>

The code under the "release:" label can only be reached after se_cmd has
been set to a non-NULL value. Hence remove the if (se_cmd) test.  Keep the
else-part since calling transport_generic_free_cmd() is not necessary for a
command that has not been submitted to the core.
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Fixes: 4d3895d5 ("target/tcm_loop: Merge struct tcm_loop_cmd and struct tcm_loop_tmr")
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NMike Christie <mchristi@redhat.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Since most target drivers do not use the second fabric_make_tpg() argument
("group") and since it is trivial to derive the group pointer from the wwn
pointer, do not pass the group pointer to fabric_make_tpg().
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NMike Christie <mchristi@redhat.com>
Cc: Felipe Balbi <felipe.balbi@linux.intel.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Fixes: e48354ce ("iscsi-target: Add iSCSI fabric support for target v4.1")
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NMike 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: NMartin K. Petersen <martin.petersen@oracle.com>

Instead of calling __iscsit_free_cmd() from inside iscsit_aborted_task() if
a command has been aborted and from inside iscsit_free_cmd() if a command
has not been aborted, call __iscsit_free_cmd() from inside
lio_release_cmd(). The latter function is namely called for all commands
once the reference count has dropped to zero.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NMike Christie <mchristi@redhat.com>
Cc: Varun Prakash <varun@chelsio.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Instead of embedding the completion that is used for waiting for command
completion in struct se_cmd, let the context that waits for command
completion allocate it. This makes it possible to have a single code path
for non-aborted and aborted commands in target_release_cmd_kref() and
avoids that transport_generic_free_cmd() has to call
cmd->se_tfo->release_cmd() directly. This patch does not change any
functionality. Note: transport_generic_free_cmd() only waits until the
se_cmd reference count has reached zero after it has set both
CMD_T_FABRIC_STOP and CMD_T_ABORTED.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NMike Christie <mchristi@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Since target_wait_free_cmd() skips TMFs with no associated LUN, it is safe
to call that function for such commands. Use this to simplify
transport_generic_free_cmd(). The only functional change in this patch is
that CMD_T_FABRIC_STOP gets set for TMFs with no associated LUN by
transport_generic_free_cmd().
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NMike Christie <mchristi@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Move identical code outside an if/else statement. This patch does not
change any functionality.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NMike Christie <mchristi@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

For the two calls to transport_cmd_finish_abort() outside
core_tmr_handle_tas_abort() it is guaranteed that CMD_T_TAS is not set. Use
this property to fold core_tmr_handle_tas_abort() into
transport_cmd_finish_abort(). This patch does not change any functionality.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NMike Christie <mchristi@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The code that can set CMD_T_TAS is executed by the same thread as the
thread that executes core_tmr_handle_tas_abort(). That means that no
locking is needed to check CMD_T_TAS from inside
core_tmr_handle_tas_abort(). This patch does not change any functionality.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NMike Christie <mchristi@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Document those aspects of transport_cmd_check_stop_to_fabric() and
transport_generic_free_cmd() of which it is nontrivial to derive these from
their implementation.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NMike Christie <mchristi@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Target drivers must call target_sess_cmd_list_set_waiting() and
target_wait_for_sess_cmds() before freeing a session. Since freeing a
session is only safe after all commands that are associated with a session
have finished, make target_wait_for_sess_cmds() also wait for commands that
are being aborted. Instead of setting a flag in each pending command from
target_sess_cmd_list_set_waiting() and waiting in
target_wait_for_sess_cmds() on a per-command completion, only set a
per-session flag in the former function and wait on a per-session
completion in the latter function. This change is safe because once a SCSI
initiator system has submitted a command a target system is always allowed
to execute it to completion. See also commit 0f4a9431 ("target: Fix
remote-port TMR ABORT + se_cmd fabric stop").

This patch is based on the following two patches:

* Bart Van Assche, target: Simplify session shutdown code, February 19, 2015
  (https://github.com/bvanassche/linux/commit/8df5463d7d7619f2f1b70cfe5172eaef0aa52815).

* Christoph Hellwig, target: Rework session shutdown code, December 7, 2015
  (http://thread.gmane.org/gmane.linux.scsi.target.devel/10695).
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NMike Christie <mchristi@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Other than initializing xcopy_pt_sess.sess_wait_list, this patch does not
change any functionality.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NMike 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: NMartin K. Petersen <martin.petersen@oracle.com>

Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NMike Christie <mchristi@redhat.com>
Cc: Mike Christie <mchristi@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This patch does not change any functionality but makes the next patch
easier to read.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NMike Christie <mchristi@redhat.com>
Cc: Mike Christie <mchristi@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

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: NBart Van Assche <bart.vanassche@wdc.com>
[Rebased to handle conflict withe target_find_device removal]
Signed-off-by: NMike Christie <mchristi@redhat.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Some target code uses config_item_name() while other code accesses .ci_name
directly. Make the target code consistent by switching to
config_item_name().
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NMike Christie <mchristi@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

32872863 ("scsi: avoid to hold host-wide counter of host_busy for
scsi_mq") adds one extra check on scsi_host_busy(shost) in
scsi_host_queue_ready(), which is wrong and not necessary, can causes
booting stall on LSI53c895A.

So remove the check.

Cc: Omar Sandoval <osandov@fb.com>,
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>,
Cc: James Bottomley <james.bottomley@hansenpartnership.com>,
Cc: Christoph Hellwig <hch@lst.de>,
Cc: Don Brace <don.brace@microsemi.com>
Cc: Kashyap Desai <kashyap.desai@broadcom.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Laurence Oberman <loberman@redhat.com>
Cc: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Guenter Roeck <linux@roeck-us.net>
Reported-by: NGuenter Roeck <linux@roeck-us.net>
Fixes: 32872863 ("scsi: avoid to hold host-wide counter of host_busy for scsi_mq")
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Tested-by: NGuenter Roeck <linux@roeck-us.net>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

In the scsi_transport_srp implementation it cannot be avoided to
iterate over a klist from atomic context when using the legacy block
layer instead of blk-mq. Hence this patch that makes it safe to use
klists in atomic context. This patch avoids that lockdep reports the
following:

WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected
 Possible interrupt unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&(&k->k_lock)->rlock);
                               local_irq_disable();
                               lock(&(&q->__queue_lock)->rlock);
                               lock(&(&k->k_lock)->rlock);
  <Interrupt>
    lock(&(&q->__queue_lock)->rlock);

stack backtrace:
Workqueue: kblockd blk_timeout_work
Call Trace:
 dump_stack+0xa4/0xf5
 check_usage+0x6e6/0x700
 __lock_acquire+0x185d/0x1b50
 lock_acquire+0xd2/0x260
 _raw_spin_lock+0x32/0x50
 klist_next+0x47/0x190
 device_for_each_child+0x8e/0x100
 srp_timed_out+0xaf/0x1d0 [scsi_transport_srp]
 scsi_times_out+0xd4/0x410 [scsi_mod]
 blk_rq_timed_out+0x36/0x70
 blk_timeout_work+0x1b5/0x220
 process_one_work+0x4fe/0xad0
 worker_thread+0x63/0x5a0
 kthread+0x1c1/0x1e0
 ret_from_fork+0x24/0x30

See also commit c9ddf734 ("scsi: scsi_transport_srp: Fix shost to
rport translation").
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: James Bottomley <jejb@linux.vnet.ibm.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>