[ Upstream commit 1cd8e751d9 ]
If the device shows up as read-only configuration, skip the clearing of the
state as the context must be preserved for device re-enable after being
disabled.
Fixes: 0dcfe41e9a ("dmanegine: idxd: cleanup all device related bits after disabling device")
Reported-by: Tony Zhu <tony.zhu@intel.com>
Tested-by: Tony Zhu <tony.zhu@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/164971479479.2200566.13980022473526292759.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit bc3452cdfc ]
When retries is compared to wq->enqcmds_retries each loop of idxd_enqcmds(),
wq->enqcmds_retries can potentially changed by user. Assign the value
of retries to wq->enqcmds_retries during initialization so it is the
original value set when entering the function.
Fixes: 7930d85535 ("dmaengine: idxd: add knob for enqcmds retries")
Suggested-by: Dave Hansen <dave.hansen@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/165031760154.3658664.1983547716619266558.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 5d9d16e5aa ]
wq->enqcmds_retries is defined as unsigned int. However, retries on the
stack is defined as int. Change retries to unsigned int to compare the same
type.
Fixes: 7930d85535 ("dmaengine: idxd: add knob for enqcmds retries")
Suggested-by: Thiago Macieira <thiago.macieira@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/165031747059.3658198.6035308204505664375.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 12e45e8955 ]
There are certain parts of WQ that needs to be cleaned up even after WQ is
disabled during the device disable. Those are the unchangeable parts for a
WQ when the device is still enabled. Move the cleanup outside of WQ state
check. Remove idxd_wq_disable_cleanup() inside idxd_wq_device_reset_cleanup()
since only the unchangeable parts need to be cleared.
Fixes: 0f225705cf ("dmaengine: idxd: fix wq settings post wq disable")
Reported-by: Tony Zhu <tony.zhu@intel.com>
Tested-by: Tony Zhu <tony.zhu@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/164919561905.1455025.13542366389944678346.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit ea7c8f598c ]
When clearing the group configurations, the driver fails to restore the
default setting for DSA 1.x based devices. Add defaults in
idxd_groups_clear_state() for traffic class configuration.
Fixes: ade8a86b51 ("dmaengine: idxd: Set defaults for GRPCFG traffic class")
Reported-by: Binuraj Ravindran <binuraj.ravindran@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/164304123369.824298.6952463420266592087.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
The following sysfs attributes will be obsolete due to the name change of
tokens to read buffers:
max_tokens
token_limit
group/tokens_allowed
group/tokens_reserved
group/use_token_limit
Create new entries and have old entry print warning of deprecation.
New attributes to replace the token ones:
max_read_buffers
read_buffer_limit
group/read_buffers_allowed
group/read_buffers_reserved
group/use_read_buffer_limit
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/163951339488.2988321.2424012059911316373.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
DSA spec v1.2 has changed the term of "bandwidth tokens" to "read buffers"
in order to make the concept clearer. Deprecate bandwidth token
naming in the driver and convert to read buffers in order to match with
the spec and reduce confusion when reading the spec.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/163951338932.2988321.6162640806935567317.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
By the spec, wq size and group association is not changeable unless device
is disabled. Exclude clearing the shadow copy on wq disable/reset. This
allows wq type to be changed after disable to be re-enabled.
Move the size and group association to its own cleanup and only call it
during device disable.
Fixes: 0dcfe41e9a ("dmanegine: idxd: cleanup all device related bits after disabling device")
Reported-by: Lucas Van <lucas.van@intel.com>
Tested-by: Lucas Van <lucas.van@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/163951291732.2987775.13576571320501115257.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Change the driver where WQ interrupt is requested only when wq is being
enabled. This new scheme set things up so that request_threaded_irq() is
only called when a kernel wq type is being enabled. This also sets up for
future interrupt request where different interrupt handler such as wq
occupancy interrupt can be setup instead of the wq completion interrupt.
Not calling request_irq() until the WQ actually needs an irq also prevents
wasting of CPU irq vectors on x86 systems, which is a limited resource.
idxd_flush_pending_descs() is moved to device.c since descriptor flushing
is now part of wq disable rather than shutdown().
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/163942149487.2412839.6691222855803875848.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The descriptor flushing for shutdown is not holding the irq_entry list
lock. If there's ongoing interrupt completion handling, this can corrupt
the list. Add locking to protect list walking. Also refactor the code so
it's more compact.
Fixes: 8f47d1a5e5 ("dmaengine: idxd: connect idxd to dmaengine subsystem")
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/163942148935.2412839.18282664745572777280.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
With irq_entry already being associated with the wq in a 1:1 relationship,
embed the irq_entry in the idxd_wq struct and remove back pointers for
idxe_wq and idxd_device. In the process of this work, clean up the interrupt
handle assignment so that there's no decision to be made during submit
call on where interrupt handle value comes from. Set the interrupt handle
during irq request initialization time.
irq_entry 0 is designated as special and is tied to the device itself.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/163942148362.2412839.12055447853311267866.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Add a sysfs knob to allow tuning of retries for the kernel ENQCMDS
descriptor submission. While on host, it is not as likely that ENQCMDS
return busy during normal operations due to the driver controlling the
number of descriptors allocated for submission. However, when the driver is
operating as a guest driver, the chance of retry goes up significantly due
to sharing a wq with multiple VMs. A default value is provided with the
system admin being able to tune the value on a per WQ basis.
Suggested-by: Sanjay Kumar <sanjay.k.kumar@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/163820629464.2702134.7577370098568297574.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Ming reported that with the abort path of the descriptor submission, there
can be a window where a completed descriptor can be missed to be completed
by the irq completion thread:
CPU A CPU B
Submit (successful)
Submit (fail)
irq_process_work_list() // empty
llist_abort_desc()
// remove all descs from pending list
irq_process_pending_llist() // empty
exit idxd_wq_thread() with no processing
Add opportunistic descriptor completion in the abort path in order to
remove the missed completion.
Fixes: 6b4b87f2c3 ("dmaengine: idxd: fix submission race window")
Reported-by: Ming Li <ming4.li@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/163898288714.443911.16084982766671976640.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Dan reports that smatch has found idxd_wq_quiesce() is being called inside
the idxd->dev_lock. idxd_wq_quiesce() calls wait_for_completion() and
therefore it can sleep. Move the call outside of the spinlock as it does
not need device lock.
Fixes: 5b0c68c473 ("dmaengine: idxd: support reporting of halt interrupt")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/163716858508.1721911.15051495873516709923.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
"Interrupt handle revoked" is an event that happens when the driver is
running on a guest kernel and the VM is migrated to a new machine.
The device will trigger an interrupt that signals to the guest driver
that the interrupt handles need to be replaced.
The misc irq thread function calls a helper function to handle the
event. The function uses the WQ percpu_ref to quiesce the kernel
submissions. It then replaces the interrupt handles by requesting
interrupt handle command for each I/O MSIX vector. Once the handle is
updated, the driver will unblock the submission path to allow new
submissions.
The submitter will attempt to acquire a percpu_ref before submission. When
the request fails, it will wait on the wq_resurrect 'completion'.
The driver does anticipate the possibility of descriptors being submitted
before the WQ percpu_ref is killed. If a descriptor has already been
submitted, it will return with incorrect interrupt handle status. The
descriptor will be re-submitted with the new interrupt handle on the
completion path. For descriptors with incorrect interrupt handles,
completion interrupt won't be triggered.
At the completion of the interrupt handle refresh, the handling function
will call idxd_int_handle_refresh_drain() to issue drain descriptors to
each of the wq with associated interrupt handle. The drain descriptor will have
interrupt request set but without completion record. This will ensure all
descriptors with incorrect interrupt completion handle get drained and
a completion interrupt is triggered for the guest driver to process them.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Co-Developed-by: Sanjay Kumar <sanjay.k.kumar@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/163528420189.3925689.18212568593220415551.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Handle a descriptor that has been marked with invalid interrupt handle
error in status. Create a work item that will resubmit the descriptor. This
typically happens when the driver has handled the revoke interrupt handle
event and has a new interrupt handle.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/163528419601.3925689.4166517602890523193.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Add a locked version of idxd_quiesce() call so that the quiesce can be
called with a lock in situations where the lock is not held by the caller.
In the driver probe/remove path, the lock is already held, so the raw
version can be called w/o locking.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/163528418980.3925689.5841907054957931211.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The helper is called at the completion of the interrupt handle refresh
event. It issues drain descriptors to each of the wq with associated
interrupt handle. The drain descriptor will have interrupt request set but
without completion record. This will ensure all descriptors with incorrect
interrupt completion handle get drained and a completion interrupt is
triggered for the guest driver to process them.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/163528418315.3925689.7944718440052849626.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
In preparation of supporting interrupt handle revoke event, move the
interrupt handle assignment to right before the descriptor to be submitted.
This allows the interrupt handle revoke logic to assign the latest
interrupt handle on submission.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/163528417767.3925689.7730411152122952808.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Attach int_handle to irq_entry. This removes the separate management of int
handles and reduces the confusion of interating through int handles that is
off by 1 count.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/163528417065.3925689.11505755433684476288.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Refactor the completion function to allow skipping of descriptor freeing on
the submission failure path. This completely removes descriptor freeing
from the submit failure path and leave the responsibility to the caller.
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/163528416222.3925689.12859769271667814762.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The wq resources needs to be released before the kernel type is reset by
__drv_disable_wq(). With dma channels unregistered and wq quiesced, all the
wq resources for dmaengine can be freed. There is no need to wait until wq
is disabled. With the wq->type being reset to "unknown", the driver is
skipping the freeing of the resources.
Fixes: 0cda4f6986 ("dmaengine: idxd: create dmaengine driver for wq 'device'")
Reported-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Tested-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/163517405099.3484556.12521975053711345244.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
According to core-api/dma-api-howto.rst, the address from
dma_alloc_coherent is gauranteed to align to the smallest PAGE_SIZE order.
That supercedes the 64B/32B alignment requirement of the completion record.
Remove alignment adjustment code.
Tested-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/163517396063.3484297.7494385225280705372.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Device reset clears the MSIXPERM table and the device registers. Re-program
the MSIXPERM table and re-enable the error interrupts post reset.
Fixes: 745e92a6d8 ("dmaengine: idxd: idxd: move remove() bits for idxd 'struct device' to device.c")
Reported-by: Sanjay Kumar <sanjay.k.kumar@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/163054188513.2853562.12077053294595278181.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Using list_move_tail() instead of list_del() + list_add_tail()
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Bixuan Cui <cuibixuan@huawei.com>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20210908092826.67765-1-cuibixuan@huawei.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
percpu_ref_tryget_live() is safe to call as long as ref is between init and
exit according to the function comment. Move percpu_ref_exit() so it is
called after the dma channel is no longer valid to ensure this holds true.
Fixes: 93a40a6d74 ("dmaengine: idxd: add percpu_ref to descriptor submission path")
Suggested-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/163294293832.914350.10326422026738506152.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The spinlock is not being used in hard interrupt context. There is no need
to disable irq when acquiring the lock. The interrupt thread handler also
is not in bottom half context, therefore we can also remove disabling of
the bh. Convert all dev_lock acquisition to plain spin_lock() calls.
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162984026772.1939166.11504067782824765879.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The cmd_lock spinlock is not being used in hard interrupt context. There is
no need to disable irq when acquiring the lock. Convert all cmd_lock
acquisition to plain spin_lock() calls.
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162984027930.1939209.15758413737332339204.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
DSA spec says WQ priv bit is 0 if the Privileged Mode Enable field of the
PCI Express PASID capability is 0 and pasid is enabled. Make sure that the
WQCFG priv field is set correctly according to usage type. Reject config if
setting up kernel WQ type and no support. Also add the correct priv setup
for a descriptor.
Fixes: 484f910e93 ("dmaengine: idxd: fix wq config registers offset programming")
Cc: Ramesh Thomas <ramesh.thomas@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162939084657.903168.14160019185148244596.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Since submission is sent to limited portal, the actual wq size for shared
wq is set by the threshold rather than the wq size. When the wq type is
shared, set the allocated descriptors to the threshold.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162827151733.3459223.3829837172226042408.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The submission path for dmaengine API does not do descriptor freeing on
failure. Also, with the abort mechanism, the freeing of descriptor happens
when the abort callback is completed. Therefore free descriptor on all
error paths for submission call to make things consistent. Also remove the
double free that would happen on abort in idxd_dma_tx_submit() call.
Fixes: 6b4b87f2c3 ("dmaengine: idxd: fix submission race window")
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162827146072.3459011.10255348500504659810.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The list lock is never acquired in interrupt context. Therefore there is no
need to disable interrupts. Remove interrupt flags for lock operations.
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162826417450.3454650.3733188117742416238.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The interrupt thread handler currently loops forever to process outstanding
completions. This causes either an "irq X: nobody cared" kernel splat or
the NMI watchdog kicks in due to running too long in the function. The irq
thread handler is expected to run again after exiting if there are
interrupts fired while the thread handler is running. So the handler code
can process all the completed I/O in a single pass and exit without losing
the follow on completed I/O.
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162802977005.3084234.11836261157026497585.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The block on fault flag is not cleared when we disable or reset wq. This
causes it to remain set if the user does not clear it on the next
configuration load. Add clear of flag in dxd_wq_disable_cleanup()
routine.
Fixes: da32b28c95 ("dmaengine: idxd: cleanup workqueue config after disabling")
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162803023553.3086015.8158952172068868803.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
'device_driver_attach()' dereferences its first argument (i.e. 'alt_drv')
so it must not be NULL.
Simplify the error handling logic about NULL 'alt_drv' in order to be
more robust and future-proof.
Fixes: 568b212646 ("dmaengine: idxd: fix uninit var for alt_drv")
Fixes: 6e7f3ee97b ("dmaengine: idxd: move dsa_drv support to compatible mode")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/77f0dc4f3966591d1f0cffb614a94085f8895a85.1627560174.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Coverity static analysis of linux-next found issue.
The check (status == IDXD_COMP_DESC_ABORT) is always false since status
was previously masked with 0x7f and IDXD_COMP_DESC_ABORT is 0xff.
Fixes: 6b4b87f2c3 ("dmaengine: idxd: fix submission race window")
Reported-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162698465160.3560828.18173186265683415384.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Enabling device and wq returns standard errno and that does not provide
enough details to indicate what exactly failed. The hardware command status
is only 8bits. Expand the command status to 32bits and use the upper 16
bits to define software errors to provide more details on the exact
failure. Bit 31 will be used to indicate the error is software set as the
driver is using some of the spec defined hardware error as well.
Cc: Ramesh Thomas <ramesh.thomas@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162681373579.1968485.5891788397526827892.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The device submission portal is on a 4k page and any of those 64bit aligned
address on the page can be used for descriptor submission. By rotating the
offset through the 4k range and prevent successive writes to the same MMIO
address, performance improvement is observed through testing.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162681372446.1968485.10634280461681015569.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The sbitmap wait and allocate routine checks the index that is returned
from sbitmap_queue_get(). It should be idxd >= 0 as 0 is also a valid
index. This fixes issue where submission path hangs when WQ size is 1.
Fixes: 0705107fcc ("dmaengine: idxd: move submission to sbitmap_queue")
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/162697645067.3478714.506720687816951762.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
