Commit Graph

112844 Commits

Author SHA1 Message Date
Borislav Petkov
ad3bc25a32 x86/kernel: Fix more -Wmissing-prototypes warnings
... with the goal of eventually enabling -Wmissing-prototypes by
default. At least on x86.

Make functions static where possible, otherwise add prototypes or make
them visible through includes.

asm/trace/ changes courtesy of Steven Rostedt <rostedt@goodmis.org>.

Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> # ACPI + cpufreq bits
Cc: Andrew Banman <andrew.banman@hpe.com>
Cc: Dimitri Sivanich <dimitri.sivanich@hpe.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mike Travis <mike.travis@hpe.com>
Cc: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yi Wang <wang.yi59@zte.com.cn>
Cc: linux-acpi@vger.kernel.org
2018-12-08 12:24:35 +01:00
Dan Carpenter
29cadd2bb6 scsi: Fix a harmless double shift bug
Smatch generates a warning:

    drivers/scsi/scsi_lib.c:1656 scsi_mq_done() warn: test_bit() takes a bit number

The problem is that SCMD_STATE_COMPLETE is supposed to be bit number 0
and not a mask like "(1 << 0)".  It is used like this:

        if (test_and_set_bit(SCMD_STATE_COMPLETE, &scmd->state))

The test_and_set_bit() has a shift built in so it's a double left shift
and uses bit number 1 instead of number 0.  This bug is harmless because
it's done consistently and it doesn't clash with any other flags.

Fixes: f1342709d1 ("scsi: Do not rely on blk-mq for double completions")
Reviewed-by: Keith Busch <keith.busch@intel.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:27:01 -07:00
Keith Busch
49cd84b6f8 nvme: implement Enhanced Command Retry
A controller may have an internal state that is not able to successfully
process commands for a short duration. In such states, an immediate
command requeue is expected to fail. The driver may exceed its max
retry count, which permanently ends the command in failure when the same
command would succeed after waiting for the controller to be ready.

NVMe ratified TP 4033 provides a delay hint in the completion status
code for failed commands. Implement the retry delay based on the command
completion status and the controller's requested delay.

Note that requeued commands are handled per request_queue, not per
individual request. If multiple commands fail, the controller should
consistently report the desired delay time for retryable commands in
all CQEs, otherwise the requeue list may be kicked too soon.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:58 -07:00
Sagi Grimberg
9b95d2fb85 nvmet: expose support for fabrics SQ flow control disable in treq
Technical Proposal introduces an indication for SQ flow control
disable support. Expose it since we are able to operate in this mode.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:57 -07:00
Sagi Grimberg
0445e1b5a2 nvmet: don't override treq upon modification.
Only override the allowed parts of it.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
[hch: slight tweak to the NVME_TREQ_SECURE_CHANNEL_MASK definition]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:57 -07:00
Sagi Grimberg
e6a622fd6d nvmet: support fabrics sq flow control
Technical proposal 8005 "fabrics SQ flow control" introduces a mode
where a host and controller agree to omit sq_head pointer updates
when sending nvme completions.

In case the host indicated desire to operate in this mode (connect attribute)
the controller will return back a connect completion with sq_head value
of 0xffff as indication that it will omit sq_head pointer updates.

This mode saves us an atomic update in the I/O path.

Reviewed-by: Hannes Reinecke <hare@suse.com>
[hch: suggested better implementation]
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:57 -07:00
James Smart
6e2e312ea7 nvmet-fc: remove the IN_ISR deferred scheduling options
All target lldd's call the cmd receive and op completions in non-isr
thread contexts. As such the IN_ISR options are not necessary.
Remove the functionality and flags, which also removes cpu assignments
to queues.

Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:57 -07:00
Jay Sternberg
f301c2b136 nvmet: add defines for discovery change async events
Add AEN/AER values as defined by the specification

Signed-off-by: Jay Sternberg <jay.e.sternberg@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:56 -07:00
Jay Sternberg
7114ddeb40 nvmet: change aen mask functions to use bit numbers
Functions nvmet_aen_disabled and nvmet_clear_aen were using
values not bit numbers ie 1 << 9 not 9 for bit function clear_bit
and test_and_set_bit.

Signed-off-by: Jay Sternberg <jay.e.sternberg@intel.com>
Reviewed-by: Phil Cayton <phil.cayton@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:56 -07:00
Sagi Grimberg
6e3ca03ee9 nvme: support traffic based keep-alive
If the controller supports traffic based keep alive, we restart the keep
alive timer if any admin or io commands was completed during the kato
period.  This prevents a possible starvation of keep alive commands in
the presence of heavy traffic as in such case, we already have a health
indication from the host perspective.

Only set a comp_seen indicator in case the controller supports keep
alive to minimize the overhead for pci controllers.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:55 -07:00
Sagi Grimberg
12b2117161 nvme: introduce ctrl attributes enumeration
We are growing more controller attributes, so use a proper enumeration
for it.  For now just add the 128-bit hostid which we support.

Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:55 -07:00
Dennis Zhou
4705de735b blkcg: put back rcu lock in blkcg_bio_issue_check()
I was a little overzealous in removing the rcu_read_lock() call from
blkcg_bio_issue_check() and it broke blk-throttle. Put it back.

Fixes: e35403a034bf ("blkcg: associate blkg when associating a device")
Signed-off-by: Dennis Zhou <dennis@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:38 -07:00
Dennis Zhou
7754f669ff blkcg: rename blkg_try_get() to blkg_tryget()
blkg reference counting now uses percpu_ref rather than atomic_t. Let's
make this consistent with css_tryget. This renames blkg_try_get to
blkg_tryget and now returns a bool rather than the blkg or %NULL.

Signed-off-by: Dennis Zhou <dennis@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:38 -07:00
Dennis Zhou
7fcf2b033b blkcg: change blkg reference counting to use percpu_ref
Every bio is now associated with a blkg putting blkg_get, blkg_try_get,
and blkg_put on the hot path. Switch over the refcnt in blkg to use
percpu_ref.

Signed-off-by: Dennis Zhou <dennis@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:38 -07:00
Dennis Zhou
6f70fb6618 blkcg: remove bio_disassociate_task()
Now that a bio only holds a blkg reference, so clean up is simply
putting back that reference. Remove bio_disassociate_task() as it just
calls bio_disassociate_blkg() and call the latter directly.

Signed-off-by: Dennis Zhou <dennis@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:38 -07:00
Dennis Zhou
fc5a828bfa blkcg: remove additional reference to the css
The previous patch in this series removed carrying around a pointer to
the css in blkg. However, the blkg association logic still relied on
taking a reference on the css to ensure we wouldn't fail in getting a
reference for the blkg.

Here the implicit dependency on the css is removed. The association
continues to rely on the tryget logic walking up the blkg tree. This
streamlines the three ways that association can happen: normal, swap,
and writeback.

Signed-off-by: Dennis Zhou <dennis@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:37 -07:00
Dennis Zhou
db6638d7d1 blkcg: remove bio->bi_css and instead use bio->bi_blkg
Prior patches ensured that any bio that interacts with a request_queue
is properly associated with a blkg. This makes bio->bi_css unnecessary
as blkg maintains a reference to blkcg already.

This removes the bio field bi_css and transfers corresponding uses to
access via bi_blkg.

Signed-off-by: Dennis Zhou <dennis@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:37 -07:00
Dennis Zhou
fd42df305f blkcg: associate writeback bios with a blkg
One of the goals of this series is to remove a separate reference to
the css of the bio. This can and should be accessed via bio_blkcg(). In
this patch, wbc_init_bio() now requires a bio to have a device
associated with it.

Signed-off-by: Dennis Zhou <dennis@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:37 -07:00
Dennis Zhou
6a7f6d86a5 blkcg: associate a blkg for pages being evicted by swap
A prior patch in this series added blkg association to bios issued by
cgroups. There are two other paths that we want to attribute work back
to the appropriate cgroup: swap and writeback. Here we modify the way
swap tags bios to include the blkg. Writeback will be tackle in the next
patch.

Signed-off-by: Dennis Zhou <dennis@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:37 -07:00
Dennis Zhou
e439bedf6b blkcg: consolidate bio_issue_init() to be a part of core
bio_issue_init among other things initializes the timestamp for an IO.
Rather than have this logic handled by policies, this consolidates it to
be on the init paths (normal, clone, bounce clone).

Signed-off-by: Dennis Zhou <dennis@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:37 -07:00
Dennis Zhou
5cdf2e3fea blkcg: associate blkg when associating a device
Previously, blkg association was handled by controller specific code in
blk-throttle and blk-iolatency. However, because a blkg represents a
relationship between a blkcg and a request_queue, it makes sense to keep
the blkg->q and bio->bi_disk->queue consistent.

This patch moves association into the bio_set_dev macro(). This should
cover the majority of cases where the device is set/changed keeping the
two pointers consistent. Fallback code is added to
blkcg_bio_issue_check() to catch any missing paths.

Signed-off-by: Dennis Zhou <dennis@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:37 -07:00
Dennis Zhou
2268c0feb0 blkcg: introduce common blkg association logic
There are 3 ways blkg association can happen: association with the
current css, with the page css (swap), or from the wbc css (writeback).

This patch handles how association is done for the first case where we
are associating bsaed on the current css. If there is already a blkg
associated, the css will be reused and association will be redone as the
request_queue may have changed.

Signed-off-by: Dennis Zhou <dennis@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:36 -07:00
Dennis Zhou
beea9da07d blkcg: convert blkg_lookup_create() to find closest blkg
There are several scenarios where blkg_lookup_create() can fail such as
the blkcg dying, request_queue is dying, or simply being OOM. Most
handle this by simply falling back to the q->root_blkg and calling it a
day.

This patch implements the notion of closest blkg. During
blkg_lookup_create(), if it fails to create, return the closest blkg
found or the q->root_blkg. blkg_try_get_closest() is introduced and used
during association so a bio is always attached to a blkg.

Signed-off-by: Dennis Zhou <dennis@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:36 -07:00
Dennis Zhou
b978962ad4 blkcg: update blkg_lookup_create() to do locking
To know when to create a blkg, the general pattern is to do a
blkg_lookup() and if that fails, lock and do the lookup again, and if
that fails finally create. It doesn't make much sense for everyone who
wants to do creation to write this themselves.

This changes blkg_lookup_create() to do locking and implement this
pattern. The old blkg_lookup_create() is renamed to
__blkg_lookup_create().  If a call site wants to do its own error
handling or already owns the queue lock, they can use
__blkg_lookup_create(). This will be used in upcoming patches.

Signed-off-by: Dennis Zhou <dennis@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Liu Bo <bo.liu@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:36 -07:00
Dennis Zhou
0fe061b9f0 blkcg: fix ref count issue with bio_blkcg() using task_css
The bio_blkcg() function turns out to be inconsistent and consequently
dangerous to use. The first part returns a blkcg where a reference is
owned by the bio meaning it does not need to be rcu protected. However,
the third case, the last line, is problematic:

	return css_to_blkcg(task_css(current, io_cgrp_id));

This can race against task migration and the cgroup dying. It is also
semantically different as it must be called rcu protected and is
susceptible to failure when trying to get a reference to it.

This patch adds association ahead of calling bio_blkcg() rather than
after. This makes association a required and explicit step along the
code paths for calling bio_blkcg(). In blk-iolatency, association is
moved above the bio_blkcg() call to ensure it will not return %NULL.

BFQ uses the old bio_blkcg() function, but I do not want to address it
in this series due to the complexity. I have created a private version
documenting the inconsistency and noting not to use it.

Signed-off-by: Dennis Zhou <dennis@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:36 -07:00
Jens Axboe
6e0de61107 blk-mq: remove QUEUE_FLAG_POLL from default MQ flags
We only support polling if we have poll queues now, but the flag is
being set by default. Remove the default QUEUE_FLAG_POLL setting, we'll
set it in blk_mq_init_allocated_queue() if we have poll queues available
for this device.

Fixes: 6544d229bf ("block: enable polling by default if a poll map is initalized")
Reported-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-07 22:26:36 -07:00
Martin K. Petersen
60a89a3ce0 scsi: t10-pi: Return correct ref tag when queue has no integrity profile
Commit ddd0bc7569 ("block: move ref_tag calculation func to the block
layer") moved ref tag calculation from SCSI to a library function. However,
this change broke returning the correct ref tag for devices operating in
DIF mode since these do not have an associated block integrity profile.
This in turn caused read/write failures on PI-formatted disks attached to
an mpt3sas controller.

Fixes: ddd0bc7569 ("block: move ref_tag calculation func to the block layer")
Cc: stable@vger.kernel.org # 4.19+
Reported-by: John Garry <john.garry@huawei.com>
Tested-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2018-12-07 22:39:46 -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
2c9fa49e10 scsi: target/core: Make ABORT and LUN RESET handling synchronous
Instead of invoking target driver callback functions from the context that
handles an abort or LUN RESET task management function, only set the abort
flag from that context and perform the actual abort handling from the
context of the regular command processing flow. This approach has the
advantage that the task management code becomes much easier to read and to
verify since the number of potential race conditions against the command
processing flow is strongly reduced.

This patch has been tested by running the following two shell commands
concurrently for about ten minutes for both the iSCSI and the SRP target
drivers ($dev is an initiator device node connected with storage provided
by the target driver under test):

 * fio with data verification enabled on a filesystem mounted on top of
   $dev.

 * while true; do sg_reset -d $dev; echo -n .; sleep .1; done

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 21:22:55 -05:00
Bart Van Assche
aaa00cc93c scsi: target/core: Fix TAS handling for aborted commands
The TASK ABORTED STATUS (TAS) bit is defined as follows in SAM:
"TASK_ABORTED: this status shall be returned if a command is aborted by a
command or task management function on another I_T nexus and the control
mode page TAS bit is set to one". TAS handling is spread over the target
core and the iSCSI target driver. If a LUN RESET is received, the target
core will send the TASK_ABORTED response for all commands for which such a
response has to be sent. If an ABORT TASK is received, only the iSCSI
target driver will send the TASK_ABORTED response for the commands for
which that response has to be sent.  That is a bug since all target drivers
have to honor the TAS bit. Fix this by moving the code that handles TAS
from the iSCSI target driver into the target core. Additionally, if a
command has been aborted, instead of sending the TASK_ABORTED status from
the context that processes the SCSI command send it from the context of the
ABORT TMF.  The core_tmr_abort_task() change in this patch causes the
CMD_T_TAS flag to be set if a TASK_ABORTED status has to be sent back to
the initiator that submitted the command. If that flag has been set
transport_cmd_finish_abort() will send the TASK_ABORTED response.

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 21:22:15 -05:00
Bart Van Assche
fbbd492355 scsi: target/core: Simplify the code for aborting SCSI commands
Instead of allowing the code that aborts a SCSI command to finish before
all iSCSI data frames have been received, make that code wait until all
iSCSI data frames have been received. Introduce a new member variable in
the target driver template to communicate that information from the iSCSI
target driver to the target core. This change allows to leave out the check
whether or not it is already safe to send the TASK_ABORTED reply from
transport_send_task_abort().

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
Bart Van Assche
a014c3647a scsi: target/core: Make it possible to wait from more than one context for command completion
This patch does not change any functionality but makes the patch that makes
TMF handling synchronous easier to read.

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
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
ad669505c4 scsi: target/core: Make sure that target_wait_for_sess_cmds() waits long enough
A session must only be released after all code that accesses the session
structure has finished. Make sure that this is the case by introducing a
new command counter per session that is only decremented after the
.release_cmd() callback has finished. This patch fixes the following crash:

BUG: KASAN: use-after-free in do_raw_spin_lock+0x1c/0x130
Read of size 4 at addr ffff8801534b16e4 by task rmdir/14805
CPU: 16 PID: 14805 Comm: rmdir Not tainted 4.18.0-rc2-dbg+ #5
Call Trace:
dump_stack+0xa4/0xf5
print_address_description+0x6f/0x270
kasan_report+0x241/0x360
__asan_load4+0x78/0x80
do_raw_spin_lock+0x1c/0x130
_raw_spin_lock_irqsave+0x52/0x60
srpt_set_ch_state+0x27/0x70 [ib_srpt]
srpt_disconnect_ch+0x1b/0xc0 [ib_srpt]
srpt_close_session+0xa8/0x260 [ib_srpt]
target_shutdown_sessions+0x170/0x180 [target_core_mod]
core_tpg_del_initiator_node_acl+0xf3/0x200 [target_core_mod]
target_fabric_nacl_base_release+0x25/0x30 [target_core_mod]
config_item_release+0x9c/0x110 [configfs]
config_item_put+0x26/0x30 [configfs]
configfs_rmdir+0x3b8/0x510 [configfs]
vfs_rmdir+0xb3/0x1e0
do_rmdir+0x262/0x2c0
do_syscall_64+0x77/0x230
entry_SYSCALL_64_after_hwframe+0x49/0xbe

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
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
Stefano Brivio
e6ac64d4c4 neighbour: Avoid writing before skb->head in neigh_hh_output()
While skb_push() makes the kernel panic if the skb headroom is less than
the unaligned hardware header size, it will proceed normally in case we
copy more than that because of alignment, and we'll silently corrupt
adjacent slabs.

In the case fixed by the previous patch,
"ipv6: Check available headroom in ip6_xmit() even without options", we
end up in neigh_hh_output() with 14 bytes headroom, 14 bytes hardware
header and write 16 bytes, starting 2 bytes before the allocated buffer.

Always check we're not writing before skb->head and, if the headroom is
not enough, warn and drop the packet.

v2:
 - instead of panicking with BUG_ON(), WARN_ON_ONCE() and drop the packet
   (Eric Dumazet)
 - if we avoid the panic, though, we need to explicitly check the headroom
   before the memcpy(), otherwise we'll have corrupted slabs on a running
   kernel, after we warn
 - use __skb_push() instead of skb_push(), as the headroom check is
   already implemented here explicitly (Eric Dumazet)

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-07 16:24:40 -08:00
David Ahern
58956317c8 neighbor: Improve garbage collection
The existing garbage collection algorithm has a number of problems:

1. The gc algorithm will not evict PERMANENT entries as those entries
   are managed by userspace, yet the existing algorithm walks the entire
   hash table which means it always considers PERMANENT entries when
   looking for entries to evict. In some use cases (e.g., EVPN) there
   can be tens of thousands of PERMANENT entries leading to wasted
   CPU cycles when gc kicks in. As an example, with 32k permanent
   entries, neigh_alloc has been observed taking more than 4 msec per
   invocation.

2. Currently, when the number of neighbor entries hits gc_thresh2 and
   the last flush for the table was more than 5 seconds ago gc kicks in
   walks the entire hash table evicting *all* entries not in PERMANENT
   or REACHABLE state and not marked as externally learned. There is no
   discriminator on when the neigh entry was created or if it just moved
   from REACHABLE to another NUD_VALID state (e.g., NUD_STALE).

   It is possible for entries to be created or for established neighbor
   entries to be moved to STALE (e.g., an external node sends an ARP
   request) right before the 5 second window lapses:

        -----|---------x|----------|-----
            t-5         t         t+5

   If that happens those entries are evicted during gc causing unnecessary
   thrashing on neighbor entries and userspace caches trying to track them.

   Further, this contradicts the description of gc_thresh2 which says
   "Entries older than 5 seconds will be cleared".

   One workaround is to make gc_thresh2 == gc_thresh3 but that negates the
   whole point of having separate thresholds.

3. Clearing *all* neigh non-PERMANENT/REACHABLE/externally learned entries
   when gc_thresh2 is exceeded is over kill and contributes to trashing
   especially during startup.

This patch addresses these problems as follows:

1. Use of a separate list_head to track entries that can be garbage
   collected along with a separate counter. PERMANENT entries are not
   added to this list.

   The gc_thresh parameters are only compared to the new counter, not the
   total entries in the table. The forced_gc function is updated to only
   walk this new gc_list looking for entries to evict.

2. Entries are added to the list head at the tail and removed from the
   front.

3. Entries are only evicted if they were last updated more than 5 seconds
   ago, adhering to the original intent of gc_thresh2.

4. Forced gc is stopped once the number of gc_entries drops below
   gc_thresh2.

5. Since gc checks do not apply to PERMANENT entries, gc levels are skipped
   when allocating a new neighbor for a PERMANENT entry. By extension this
   means there are no explicit limits on the number of PERMANENT entries
   that can be created, but this is no different than FIB entries or FDB
   entries.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-07 16:03:10 -08:00
Felix Kuehling
1dde0ea95b drm/amdkfd: Add DMABuf import functionality
This is used for interoperability between ROCm compute and graphics
APIs. It allows importing graphics driver BOs into the ROCm SVM
address space for zero-copy GPU access.

The API is split into two steps (query and import) to allow user mode
to manage the virtual address space allocation for the imported buffer.

Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-12-07 18:13:54 -05:00
Christian König
a9f34c70fd drm/ttm: allow reserving more than one shared slot v3
Let's support simultaneous submissions to multiple engines.

v2: rename the field to num_shared and fix up all users
v3: rebased

Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Reviewed-by: Junwei Zhang <Jerry.Zhang@amd.com>
Reviewed-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2018-12-07 17:53:44 -05:00
Arnd Bergmann
bec2f7cbb7 y2038: futex: Add support for __kernel_timespec
This prepares sys_futex for y2038 safe calling: the native
syscall is changed to receive a __kernel_timespec argument, which
will be switched to 64-bit time_t in the future. All the internal
time handling gets changed to timespec64, and the compat_sys_futex
entry point is moved under the CONFIG_COMPAT_32BIT_TIME check
to provide compatibility for existing 32-bit architectures.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-12-07 22:19:07 +01:00
Arnd Bergmann
04e7712f44 y2038: futex: Move compat implementation into futex.c
We are going to share the compat_sys_futex() handler between 64-bit
architectures and 32-bit architectures that need to deal with both 32-bit
and 64-bit time_t, and this is easier if both entry points are in the
same file.

In fact, most other system call handlers do the same thing these days, so
let's follow the trend here and merge all of futex_compat.c into futex.c.

In the process, a few minor changes have to be done to make sure everything
still makes sense: handle_futex_death() and futex_cmpxchg_enabled() become
local symbol, and the compat version of the fetch_robust_entry() function
gets renamed to compat_fetch_robust_entry() to avoid a symbol clash.

This is intended as a purely cosmetic patch, no behavior should
change.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2018-12-07 22:19:07 +01:00
Petr Machata
43920edf3b bridge: Add br_fdb_clear_offload()
When a driver unoffloads all FDB entries en bloc, it's inefficient to
send the switchdev notification one by one. Add a helper that unsets the
offload flag on FDB entries on a given bridge port and VLAN.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-07 12:59:08 -08:00
Petr Machata
e5ff4b1952 vxlan: Add vxlan_fdb_clear_offload()
When a driver unoffloads all FDB entries en bloc, it's inefficient to
send the switchdev notification one by one. Add a helper that walks the
FDB table, unsetting the offload flag on RDST with a given VNI.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-07 12:59:08 -08:00
Petr Machata
4f89f5b535 vxlan: Add vxlan_fdb_replay()
When a VXLAN device becomes relevant to a driver (such as when it is
attached to an offloaded bridge), the driver will generally need to walk
the existing FDB entries and offload them.

Add a function vxlan_fdb_replay() to call a given notifier block for
each FDB entry with a given VNI.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-07 12:59:08 -08:00
Jason Gunthorpe
fe15bcc6e2 Merge branch 'mlx5-packet-credit-fc' into rdma.git
Danit Goldberg says:

Packet based credit mode

Packet based credit mode is an alternative end-to-end credit mode for QPs
set during their creation. Credits are transported from the responder to
the requester to optimize the use of its receive resources.  In
packet-based credit mode, credits are issued on a per packet basis.

The advantage of this feature comes while sending large RDMA messages
through switches that are short in memory.

The first commit exposes QP creation flag and the HCA capability. The
second commit adds support for a new DV QP creation flag. The last commit
report packet based credit mode capability via the MLX5DV device
capabilities.

* branch 'mlx5-packet-credit-fc':
  IB/mlx5: Report packet based credit mode device capability
  IB/mlx5: Add packet based credit mode support
  net/mlx5: Expose packet based credit mode

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-12-07 13:25:12 -07:00
Danit Goldberg
7e11b911b5 IB/mlx5: Report packet based credit mode device capability
Report packet based credit mode capability via the mlx5 DV interface.

Signed-off-by: Danit Goldberg <danitg@mellanox.com>
Reviewed-by: Majd Dibbiny <majd@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-12-07 13:22:09 -07:00
Danit Goldberg
569c665150 IB/mlx5: Add packet based credit mode support
The device can support two credit modes, message based (default) and
packet based. In order to enable packet based mode, the QP should be
created with special flag that indicates this.

This patch adds support for the new DV QP creation flag that can be used
for RC QPs in order to change the credit mode.

Signed-off-by: Danit Goldberg <danitg@mellanox.com>
Reviewed-by: Majd Dibbiny <majd@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2018-12-07 13:22:09 -07:00
Eric Anholt
36e7999dc1 drm/v3d: Document cache flushing ABI.
Right now, userspace doesn't do any L2T writes, but we should lay out
our expectations for how it works.

v2: Explicitly mention the VCD cache flushing requirements and that
    we'll flush the other caches before each of the CLs.

Signed-off-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20181203222438.25417-1-eric@anholt.net
Reviewed-by: Dave Emett <david.emett@broadcom.com>
2018-12-07 10:55:48 -08:00
Peter Hutterer
2dc702c991 HID: input: use the Resolution Multiplier for high-resolution scrolling
Windows uses a magic number of 120 for a wheel click. High-resolution
scroll wheels are supposed to use a fraction of 120 to signal smaller
scroll steps. This is implemented by the Resolution Multiplier in the
device itself.

If the multiplier is present in the report descriptor, set it to the
logical max and then use the resolution multiplier to calculate the
high-resolution events. This is the recommendation by Microsoft, see
http://msdn.microsoft.com/en-us/windows/hardware/gg487477.aspx

Note that all mice encountered so far have a logical min/max of 0/1, so
it's a binary "yes or no" to high-res scrolling anyway.

To make userspace simpler, always enable the REL_WHEEL_HI_RES bit. Where
the device doesn't support high-resolution scrolling, the value for the
high-res data will simply be a multiple of 120 every time. For userspace,
if REL_WHEEL_HI_RES is available that is the one to be used.

Potential side-effect: a device with a Resolution Multiplier applying to
other Input items will have those items set to the logical max as well.
This cannot easily be worked around but it is doubtful such devices exist.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Verified-by: Harry Cutts <hcutts@chromium.org>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
2018-12-07 16:27:13 +01:00
Peter Hutterer
5a4abb36f3 HID: core: process the Resolution Multiplier
The Resolution Multiplier is a feature report that modifies the value of
Usages within the same Logical Collection. If the multiplier is set to
anything but 1, the hardware reports (value * multiplier) for the same amount
of physical movement, i.e. the value we receive in the kernel is
pre-multiplied.

The hardware may either send a single (value * multiplier), or by sending
multiplier as many reports with the same value, or a combination of these two
options. For example, when the Microsoft Sculpt Ergonomic mouse Resolution
Multiplier is set to 12, the Wheel sends out 12 for every detent but AC Pan
sends out a value of 3 at 4 times the frequency.

The effective multiplier is based on the physical min/max of the multiplier
field, a logical min/max of [0,1] with a physical min/max of [1,8] means the
multiplier is either 1 or 8.

The Resolution Multiplier was introduced for high-resolution scrolling in
Windows Vista and is commonly used on Microsoft mice.

The recommendation for the Resolution Multiplier is to default to 1 for
backwards compatibility. This patch adds an arbitrary upper limit at 255. The
only known use case for the Resolution Multiplier is for scroll wheels where the
multiplier has to be a fraction of 120 to work with Windows.

Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Verified-by: Harry Cutts <hcutts@chromium.org>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
2018-12-07 16:27:13 +01:00