Generally target core and TCMUser seem to work fine for tape devices and
media changers. But there is at least one situation where TCMUser is not
able to support sequential access device emulation correctly.
The situation is when an initiator sends a SCSI READ CDB with a length that
is greater than the length of the tape block to read. We can distinguish
two subcases:
A) The initiator sent the READ CDB with the SILI bit being set.
In this case the sequential access device has to transfer the data from
the tape block (only the length of the tape block) and transmit a good
status. The current interface between TCMUser and the userspace does
not support reduction of the read data size by the userspace program.
The patch below fixes this subcase by allowing the userspace program to
specify a reduced data size in read direction.
B) The initiator sent the READ CDB with the SILI bit not being set.
In this case the sequential access device has to transfer the data from
the tape block as in A), but additionally has to transmit CHECK
CONDITION with the ILI bit set and NO SENSE in the sensebytes. The
information field in the sensebytes must contain the residual count.
With the below patch a user space program can specify the real read data
length and appropriate sensebytes. TCMUser then uses the se_cmd flag
SCF_TREAT_READ_AS_NORMAL, to force target core to transmit the real data
size and the sensebytes. Note: the flag SCF_TREAT_READ_AS_NORMAL is
introduced by Lee Duncan's patch "[PATCH v4] target: transport should
handle st FM/EOM/ILI reads" from Tue, 15 May 2018 18:25:24 -0700.
Signed-off-by: Bodo Stroesser <bstroesser@ts.fujitsu.com>
Acked-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This is mostly updates to the usual drivers: ufs, qedf, mpt3sas, lpfc,
xfcp, hisi_sas, cxlflash, qla2xxx. In the absence of Nic, we're also
taking target updates which are mostly minor except for the tcmu
refactor. The only real core change to worry about is the removal of
high page bouncing (in sas, storvsc and iscsi). This has been well
tested and no problems have shown up so far.
Signed-off-by: James E.J. Bottomley <jejb@linux.vnet.ibm.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 mostly updates to the usual drivers: ufs, qedf, mpt3sas, lpfc,
xfcp, hisi_sas, cxlflash, qla2xxx.
In the absence of Nic, we're also taking target updates which are
mostly minor except for the tcmu refactor.
The only real core change to worry about is the removal of high page
bouncing (in sas, storvsc and iscsi). This has been well tested and no
problems have shown up so far"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (268 commits)
scsi: lpfc: update driver version to 12.0.0.4
scsi: lpfc: Fix port initialization failure.
scsi: lpfc: Fix 16gb hbas failing cq create.
scsi: lpfc: Fix crash in blk_mq layer when executing modprobe -r lpfc
scsi: lpfc: correct oversubscription of nvme io requests for an adapter
scsi: lpfc: Fix MDS diagnostics failure (Rx < Tx)
scsi: hisi_sas: Mark PHY as in reset for nexus reset
scsi: hisi_sas: Fix return value when get_free_slot() failed
scsi: hisi_sas: Terminate STP reject quickly for v2 hw
scsi: hisi_sas: Add v2 hw force PHY function for internal ATA command
scsi: hisi_sas: Include TMF elements in struct hisi_sas_slot
scsi: hisi_sas: Try wait commands before before controller reset
scsi: hisi_sas: Init disks after controller reset
scsi: hisi_sas: Create a scsi_host_template per HW module
scsi: hisi_sas: Reset disks when discovered
scsi: hisi_sas: Add LED feature for v3 hw
scsi: hisi_sas: Change common allocation mode of device id
scsi: hisi_sas: change slot index allocation mode
scsi: hisi_sas: Introduce hisi_sas_phy_set_linkrate()
scsi: hisi_sas: fix a typo in hisi_sas_task_prep()
...
Problem:
$ cat /sys/kernel/config/target/core/user_0/block/attrib/qfull_time_out
-1
$ echo "-1" > /sys/kernel/config/target/core/user_0/block/attrib/qfull_time_out
-bash: echo: write error: Invalid argument
Fix:
This patch will help reset qfull_time_out to its default
i.e. qfull_time_out=-1.
Signed-off-by: Prasanna Kumar Kalever <prasanna.kalever@redhat.com>
Acked-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
use new netlink events helpers tcmu_netlink_init() and
tcmu_netlink_send() to refactor netlink event attribute
TCMU_ATTR_WRITECACHE(belongs to TCMU_CMD_RECONFIG_DEVICE) which is also
emulate_write_cache in configFS.
Removed tcmu_netlink_event() since we have new netlink
events helpers now.
Signed-off-by: Zhu Lingshan <lszhu@suse.com>
Acked-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
use new netlink events helpers tcmu_netlink_init() and
tcmu_netlink_send() to refactor netlink event attribute
TCMU_ATTR_DEV_SIZE(belongs to TCMU_CMD_RECONFIG_DEVICE) which is also
dev_size in configFS.
Signed-off-by: Zhu Lingshan <lszhu@suse.com>
Acked-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
use new netlink events helpers tcmu_netlink_init() and
tcmu_netlink_send() to refactor netlink event attribute
TCMU_ATTR_DEV_CFG(belongs to TCMU_CMD_RECONFIG_DEVICE) which is also
dev_config in configFS.
Signed-off-by: Zhu Lingshan <lszhu@suse.com>
Acked-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
use new netlink events helpers tcmu_netlink_init() and
tcmu_netlink_send() to refactor netlink event TCMU_CMD_REMOVED_DEVICE
Signed-off-by: Zhu Lingshan <lszhu@suse.com>
Acked-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
use new netlink events helpers tcmu_netlink_init() and
tcmu_netlink_send() to refactor netlink event TCMU_CMD_ADDED_DEVICE
Signed-off-by: Zhu Lingshan <lszhu@suse.com>
Acked-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Add new netlink events helpers tcmu_netlink_event_init() and
tcmu_netlink_event_send(). These new functions intend to replace
existing netlink events helper function tcmu_netlink_event().
The existing function tcmu_netlink_event() works well for events like
TCMU_ADDED_DEVICE and TCMU_REMOVED_DEVICE which only has one netlink
attribute. But if there is a command requires more than one attributes
to send out, we have to use a struct to adapt the paremeter
reconfig_data, it is hard to use one struct or a union in one struct to
adapt every command with different attributes, it may get long and ugly.
With the new two functions, we can call tcmu_netlink_event_init() to
initialize a netlink event, then add all attributes we need by using
nla_put_xxx(), at last use tcmu_netlink_event_send() to send it out. So
that we don't need to use a long struct or union if we want to send
mulitple attributes for different commands.
[mkp: typos]
Signed-off-by: Zhu Lingshan <lszhu@suse.com>
Acked-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Make documentation on target-supported userspace-I/O design be
usable by kernel-doc by using "DOC:". This is used in the driver-api
Documentation chapter.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
To: "Nicholas A. Bellinger" <nab@linux-iscsi.org>
Cc: linux-scsi@vger.kernel.org
Cc: target-devel@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: "James E.J. Bottomley" <jejb@linux.vnet.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Use new return type vm_fault_t for fault handler in struct
vm_operations_struct.
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The trailing semicolon is an empty statement that does no operation.
It is completely stripped out by the compiler. Removing it since it doesn't do
anything.
Signed-off-by: Luis de Bethencourt <luisbg@kernel.org>
Acked-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
If we are failing the command due to a qfull timeout we are
also freeing the tcmu command, so we cannot access it later
to get the se_cmd.
Note: The clearing of cmd->se_cmd is not needed. We do not check
it later for something like determining if the command was failed
due to a timeout. As a result I am dropping it.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch adds 2 tcmu attrs to block/unblock a device and
reset the ring buffer. They are used when the userspace
daemon has crashed or forced to shutdown while IO is executing.
On restart, the daemon can block the device so new IO is not
sent to userspace while it puts the ring in a clean state.
Notes: The reset ring opreation is specific to tcmu, but the
block one could be generic. I kept it tcmu specific, because
it requires some extra locking/state checks in the main IO
path and since other backend modules did not need this
functionality I thought only tcmu should take the perf hit.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Fix to return error code -ENOMEM from the kzalloc() error handling
case instead of 0, as done elsewhere in this function.
Fixes: 80eb876 ("tcmu: allow max block and global max blocks to be settable")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Acked-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Log cmd id that was not found in the tcmu_handle_completions
lookup failure path.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
We will always have a page mapped for cmd data if it is
valid command. If the mapping does not exist then something
bad happened in userspace and it should not proceed. This
has us return VM_FAULT_SIGBUS when this happens instead of
returning a freshly allocated paged. The latter can cause
corruption because userspace might write the pages data
overwriting valid data or return it to the initiator.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Users might have a physical system to a target so they could
have a lot more than 2 gigs of memory they want to devote to
tcmu. OTOH, we could be running in a vm and so a 2 gig
global and 1 gig per dev limit might be too high. This patch
allows the user to specify the limits.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This adds a timer, qfull_time_out, that controls how long a
device will wait for ring buffer space to open before
failing the commands in the queue. It is useful to separate
this timer from the cmd_time_out and default 30 sec one,
because for HA setups cmd_time_out may be disbled and 30
seconds is too long to wait when some OSs like ESX will
timeout commands after as little as 8 - 15 seconds.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch has tcmu internally queue cmds if its ring buffer
is full. It also makes the TCMU_GLOBAL_MAX_BLOCKS limit a
hint instead of a hard limit, so we do not have to add any
new locks/atomics in the main IO path except when IO is not
running.
This fixes the following bugs:
1. We cannot sleep from the submitting context because it might be
called from a target recv context. This results in transport level
commands timing out. For example if the ring is full, we would
sleep, and a iscsi initiator would send a iscsi ping/nop which
times out because the target's recv thread is sleeping here.
2. Devices were not fairly scheduled to run when they hit the global
limit so they could time out waiting for ring space while others
got run.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
We do not really save a lot by trying to increase thresh
a multiple of the existing value. This just simplifies the
code by increasing it to whatever is needed for the command
being executed.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
In the next patches we will call queue_cmd_ring from the submitting
context and also the completion path. This changes the queue_cmd_ring
return code so in the next patches we can return a sense_reason_t
and also signal if a command was requeued.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Add some comments to make the scatter code to be more readable,
and drop unused arg to new_iov.
Signed-off-by: Xiubo Li <lixiubo@cmss.chinamobile.com>
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
The blocks_left calculation does not account for free blocks
between 0 and thresh, so we could be queueing/waiting when
there are enough blocks free.
This has us add in the blocks between 0 and thresh as well as
at the end from thresh to DATA_BLOCK_BITS.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
scatter_data_area always returns 0, so stop checking
for errors.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
If we cannot setup a cmd because we run out of ring space
or global pages release the blocks before sleeping. This
prevents a deadlock where dev0 has waiting_blocks set and
needs N blocks, but dev1 to devX have each allocated N / X blocks
and also hit the global block limit so they went to sleep.
find_free_blocks is not able to take the sleeping dev's
blocks becaause their waiting_blocks is set and even
if it was not the block returned by find_last_bit could equal
dbi_max. The latter will probably never happen because
DATA_BLOCK_BITS is so high but in the next patches
DATA_BLOCK_BITS and TCMU_GLOBAL_MAX_BLOCKS will be settable so
it might be lower and could happen.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
No need for the commands_lock. The cmdr_lock is already held during
idr addition and deletion, so just grab it during traversal.
Note: This also fixes a issue where we should have been using at
least _bh locking in tcmu_handle_completions when taking the commands
lock to prevent the case where tcmu_handle_completions could be
interrupted by a timer softirq while the commands_lock is held.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This moves the expired command completion handling to
the unmap wq, so the next patch can use a mutex
in tcmu_check_expired_cmd.
Note:
tcmu_device_timedout's use of spin_lock_irq was not needed.
The commands_lock is used between thread context (tcmu_queue_cmd_ring
and tcmu_irqcontrol (even though this is named irqcontrol it is not
run in irq context)) and timer/bh context. In the timer/bh context
bhs are disabled, so you need to use the _bh lock calls from the
thread context callers.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
If the unmap thread has already run find_free_blocks
but not yet run prepare_to_wait when a wake_up(&unmap_wait)
call is done, the unmap thread is going to miss the wake
call. Instead of adding checks for if new waiters were added
this just has us use a work queue which will run us again
in this type of case.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Separate unmap_thread_fn to make it easier to read.
Note: this patch does not fix the bug where we might
miss a wake up call. The next patch will fix that.
This patch only separates the code into functions.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Have unmap_thread_fn use tcmu_blocks_release.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
The page addr should be update.
Signed-off-by: tangwenji <tang.wenji@zte.com.cn>
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Pull timer updates from Thomas Gleixner:
- The final conversion of timer wheel timers to timer_setup().
A few manual conversions and a large coccinelle assisted sweep and
the removal of the old initialization mechanisms and the related
code.
- Remove the now unused VSYSCALL update code
- Fix permissions of /proc/timer_list. I still need to get rid of that
file completely
- Rename a misnomed clocksource function and remove a stale declaration
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits)
m68k/macboing: Fix missed timer callback assignment
treewide: Remove TIMER_FUNC_TYPE and TIMER_DATA_TYPE casts
timer: Remove redundant __setup_timer*() macros
timer: Pass function down to initialization routines
timer: Remove unused data arguments from macros
timer: Switch callback prototype to take struct timer_list * argument
timer: Pass timer_list pointer to callbacks unconditionally
Coccinelle: Remove setup_timer.cocci
timer: Remove setup_*timer() interface
timer: Remove init_timer() interface
treewide: setup_timer() -> timer_setup() (2 field)
treewide: setup_timer() -> timer_setup()
treewide: init_timer() -> setup_timer()
treewide: Switch DEFINE_TIMER callbacks to struct timer_list *
s390: cmm: Convert timers to use timer_setup()
lightnvm: Convert timers to use timer_setup()
drivers/net: cris: Convert timers to use timer_setup()
drm/vc4: Convert timers to use timer_setup()
block/laptop_mode: Convert timers to use timer_setup()
net/atm/mpc: Avoid open-coded assignment of timer callback function
...
Pull SCSI target updates from Nicholas Bellinger:
"This series is predominantly bug-fixes, with a few small improvements
that have been outstanding over the last release cycle.
As usual, the associated bug-fixes have CC' tags for stable.
Also, things have been particularly quiet wrt new developments the
last months, with most folks continuing to focus on stability atop 4.x
stable kernels for their respective production configurations.
Also at this point, the stable trees have been synced up with
mainline. This will continue to be a priority, as production users
tend to run exclusively atop stable kernels, a few releases behind
mainline.
The highlights include:
- Fix PR PREEMPT_AND_ABORT null pointer dereference regression in
v4.11+ (tangwenji)
- Fix OOPs during removing TCMU device (Xiubo Li + Zhang Zhuoyu)
- Add netlink command reply supported option for each device (Kenjiro
Nakayama)
- cxgbit: Abort the TCP connection in case of data out timeout (Varun
Prakash)
- Fix PR/ALUA file path truncation (David Disseldorp)
- Fix double se_cmd completion during ->cmd_time_out (Mike Christie)
- Fix QUEUE_FULL + SCSI task attribute handling in 4.1+ (Bryant Ly +
nab)
- Fix quiese during transport_write_pending_qf endless loop (nab)
- Avoid early CMD_T_PRE_EXECUTE failures during ABORT_TASK in 3.14+
(Don White + nab)"
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (35 commits)
tcmu: Add a missing unlock on an error path
tcmu: Fix some memory corruption
iscsi-target: Fix non-immediate TMR reference leak
iscsi-target: Make TASK_REASSIGN use proper se_cmd->cmd_kref
target: Avoid early CMD_T_PRE_EXECUTE failures during ABORT_TASK
target: Fix quiese during transport_write_pending_qf endless loop
target: Fix caw_sem leak in transport_generic_request_failure
target: Fix QUEUE_FULL + SCSI task attribute handling
iSCSI-target: Use common error handling code in iscsi_decode_text_input()
target/iscsi: Detect conn_cmd_list corruption early
target/iscsi: Fix a race condition in iscsit_add_reject_from_cmd()
target/iscsi: Modify iscsit_do_crypto_hash_buf() prototype
target/iscsi: Fix endianness in an error message
target/iscsi: Use min() in iscsit_dump_data_payload() instead of open-coding it
target/iscsi: Define OFFLOAD_BUF_SIZE once
target: Inline transport_put_cmd()
target: Suppress gcc 7 fallthrough warnings
target: Move a declaration of a global variable into a header file
tcmu: fix double se_cmd completion
target: return SAM_STAT_TASK_SET_FULL for TCM_OUT_OF_RESOURCES
...
We added a new error path here but we forgot to drop the lock first
before returning.
Fixes: 0d44374c1a ("tcmu: fix double se_cmd completion")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
"udev->nl_reply_supported" is an int but on 64 bit arches we are writing
8 bytes of data to it so it corrupts four bytes beyond the end of the
struct.
Fixes: b849b45675 ("target: Add netlink command reply supported option for each device")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
If cmd_time_out != 0, then tcmu_queue_cmd_ring could end up
sleeping waiting for ring space, timing out and then returning
failure to lio, and tcmu_check_expired_cmd could also detect
the timeout and call target_complete_cmd on the cmd.
This patch just delays setting up the deadline value and adding
the cmd to the udev->commands idr until we have allocated ring
space and are about to send the cmd to userspace.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Currently netlink command reply support option
(TCMU_ATTR_SUPP_KERN_CMD_REPLY) can be enabled only on module
scope. Because of that, once an application enables the netlink
command reply support, all applications using target_core_user.ko
would be expected to support the netlink reply. To make matters worse,
users will not be able to add a device via configfs manually.
To fix these issues, this patch adds an option to make netlink command
reply disabled on each device through configfs. Original
TCMU_ATTR_SUPP_KERN_CMD_REPLY is still enabled on module scope to keep
backward-compatibility and used by default, however once users set
nl_reply_supported=<NAGATIVE_VALUE> via configfs for a particular
device, the device disables the netlink command reply support.
Signed-off-by: Kenjiro Nakayama <nakayamakenjiro@gmail.com>
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This patch makes a tiny change that using TCMU_DEV in
tcmu_cmd_time_out_show so it is consistent with other functions.
Signed-off-by: Kenjiro Nakayama <nakayamakenjiro@gmail.com>
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Please do not apply this to mainline directly, instead please re-run the
coccinelle script shown below and apply its output.
For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
preference to ACCESS_ONCE(), and new code is expected to use one of the
former. So far, there's been no reason to change most existing uses of
ACCESS_ONCE(), as these aren't harmful, and changing them results in
churn.
However, for some features, the read/write distinction is critical to
correct operation. To distinguish these cases, separate read/write
accessors must be used. This patch migrates (most) remaining
ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following
coccinelle script:
----
// Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and
// WRITE_ONCE()
// $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch
virtual patch
@ depends on patch @
expression E1, E2;
@@
- ACCESS_ONCE(E1) = E2
+ WRITE_ONCE(E1, E2)
@ depends on patch @
expression E;
@@
- ACCESS_ONCE(E)
+ READ_ONCE(E)
----
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: davem@davemloft.net
Cc: linux-arch@vger.kernel.org
Cc: mpe@ellerman.id.au
Cc: shuah@kernel.org
Cc: snitzer@redhat.com
Cc: thor.thayer@linux.intel.com
Cc: tj@kernel.org
Cc: viro@zeniv.linux.org.uk
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
On initial tcmu_configure_device call the info->name would
have already been allocated and set, so on the second call
make sure to free it first.
Reported-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
For most case the sg->length equals to PAGE_SIZE, so this bug won't
be triggered. Otherwise this will crash the kernel, for example when
all segments' sg->length equal to 1K.
Signed-off-by: Xiubo Li <lixiubo@cmss.chinamobile.com>
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Remove useless blank line and code and at the same time add one error
path to catch the errors.
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Xiubo Li <lixiubo@cmss.chinamobile.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Currently when there is a reconfig, the uio_info->name
does not get updated to reflect the change in the dev_config
name change.
On restart tcmu-runner there will be a mismatch between
the dev_config string in uio and the tcmu structure that contains
the string. When this occurs it'll reload the one in uio
and you lose the reconfigured device path.
v2: Created a helper function for the updating of uio_info
Signed-off-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
We were just copying the sense to the cmd sense_buffer and
did not implement a transport_complete or set the
SCF_TRANSPORT_TASK_SENSE, so the sense was ignored.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
When feeding the tcmu's cmd ring, we need to flush the dcache page
for the cmd entry to make sure these kernel stores are visible to
user space mappings of that page.
For the none PAD cmd entry, this will be flushed at the end of the
tcmu_queue_cmd_ring().
Signed-off-by: Xiubo Li <lixiubo@cmss.chinamobile.com>
Reviewed-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
bstroesser@ts.fujitsu.com