DSA spec states that when Request Interrupt Handle and Release Interrupt
Handle command bits are set in the CMDCAP register, these device commands
must be supported by the driver.
The interrupt handle is programmed in a descriptor. When Request Interrupt
Handle is not supported, the interrupt handle is the index of the desired
entry in the MSI-X table. When the command is supported, driver must use
the command to obtain a handle to be programmed in the submitted
descriptor.
A requested handle may be revoked. After the handle is revoked, any use of
the handle will result in Invalid Interrupt Handle error.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/161894439422.3202472.17579543737810265471.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The read-only configuration mode is defined by the DSA spec as a mode of
the device WQ configuration. When GENCAP register bit 31 is set to 0,
the device is in RO mode and group configuration and some fields of the
workqueue configuration registers are read-only and reflect the fixed
configuration of the device. Add support for RO mode. The driver will
load the values from the registers directly setup all the internally
cached data structures based on the device configuration.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/161894438847.3202472.6317563824045432727.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Current submission path has no way to restrict the submitter from
stop submiting on shutdown path or wq disable path. This provides a way to
quiesce the submission path.
Modeling after 'struct reqeust_queue' usage of percpu_ref. One of the
abilities of per_cpu reference counting is the ability to stop new
references from being taken while awaiting outstanding references to be
dropped. On wq shutdown, we want to block any new submissions to the kernel
workqueue and quiesce before disabling. The percpu_ref allows us to block
any new submissions and wait for any current submission calls to finish
submitting to the workqueue.
A percpu_ref is embedded in each idxd_wq context to allow control for
individual wq. The wq->wq_active counter is elevated before calling
movdir64b() or enqcmds() to submit a descriptor to the wq and dropped once
the submission call completes. The function is gated by
percpu_ref_tryget_live(). On shutdown with percpu_ref_kill() called, any
new submission would be blocked from acquiring a ref and failed. Once all
references are dropped for the wq, shutdown can continue.
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/161894438293.3202472.14894701611500822232.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
There is no need to have an additional bus for the IAX device. The removal
of IAX will change user ABI as /sys/bus/iax will no longer exist.
The iax device will be moved to the dsa bus. The device id for dsa and
iax will now be combined rather than unique for each device type in order
to accommodate the iax devices. This is in preparation for fixing the
sub-driver code for idxd. There's no hardware deployment for Sapphire
Rapids platform yet, which means that users have no reason to have
developed scripts against this ABI. There is some exposure to
released versions of accel-config, but those are being fixed up and
an accel-config upgrade is reasonable to get IAX support. As far as
accel-config is concerned IAX support starts when these devices appear
under /sys/bus/dsa, and old accel-config just assumes that an empty /
missing /sys/bus/iax just means a lack of platform support.
Fixes: f25b463883 ("dmaengine: idxd: add IAX configuration support in the IDXD driver")
Suggested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/161852988298.2203940.4529909758034944428.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The char device setup and cleanup has device lifetime issues regarding when
parts are initialized and cleaned up. The initialization of struct device is
done incorrectly. device_initialize() needs to be called on the 'struct
device' and then additional changes can be added. The ->release() function
needs to be setup via device_type before dev_set_name() to allow proper
cleanup. The change re-parents the cdev under the wq->conf_dev to get
natural reference inheritance. No known dependency on the old device path exists.
Reported-by: Jason Gunthorpe <jgg@nvidia.com>
Fixes: 42d279f913 ("dmaengine: idxd: add char driver to expose submission portal to userland")
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/161852987721.2203940.1478218825576630810.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The devm managed lifetime is incompatible with 'struct device' objects that
resides in idxd context. This is one of the series that clean up the idxd
driver 'struct device' lifetime. Fix idxd->conf_dev 'struct device'
lifetime. Address issues flagged by CONFIG_DEBUG_KOBJECT_RELEASE.
Add release functions in order to free the allocated memory at the
appropriate time.
Reported-by: Jason Gunthorpe <jgg@nvidia.com>
Fixes: bfe1d56091 ("dmaengine: idxd: Init and probe for Intel data accelerators")
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/161852985319.2203940.4650791514462735368.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The devm managed lifetime is incompatible with 'struct device' objects that
resides in idxd context. This is one of the series that clean up the idxd
driver 'struct device' lifetime. Remove pcim_* management of the PCI device
and the ioremap of MMIO BAR and replace with unmanaged versions. This is
for consistency of removing all the pcim/devm based calls.
Reported-by: Jason Gunthorpe <jgg@nvidia.com>
Fixes: bfe1d56091 ("dmaengine: idxd: Init and probe for Intel data accelerators")
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/161852984150.2203940.8043988289748519056.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The devm managed lifetime is incompatible with 'struct device' objects that
resides in idxd context. This is one of the series that clean up the idxd
driver 'struct device' lifetime. Remove embedding of dma_device and dma_chan
in idxd since it's not the only interface that idxd will use. The freeing of
the dma_device will be managed by the ->release() function.
Reported-by: Jason Gunthorpe <jgg@nvidia.com>
Fixes: bfe1d56091 ("dmaengine: idxd: Init and probe for Intel data accelerators")
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Link: https://lore.kernel.org/r/161852983001.2203940.14817017492384561719.stgit@djiang5-desk3.ch.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
There are calls to idxd_cmd_exec that pass a null status pointer however
a recent commit has added an assignment to *status that can end up
with a null pointer dereference. The function expects a null status
pointer sometimes as there is a later assignment to *status where
status is first null checked. Fix the issue by null checking status
before making the assignment.
Addresses-Coverity: ("Explicit null dereferenced")
Fixes: 89e3becd8f ("dmaengine: idxd: check device state before issue command")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20210415110654.1941580-1-colin.king@canonical.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
In the first list_for_each_entry() macro of dma_async_device_register,
it gets the chan from list and calls __dma_async_device_channel_register
(..,chan). We can see that chan->local is allocated by alloc_percpu() and
it is freed chan->local by free_percpu(chan->local) when
__dma_async_device_channel_register() failed.
But after __dma_async_device_channel_register() failed, the caller will
goto err_out and freed the chan->local in the second time by free_percpu().
The cause of this problem is forget to set chan->local to NULL when
chan->local was freed in __dma_async_device_channel_register(). My
patch sets chan->local to NULL when the callee failed to avoid double free.
Fixes: d2fb0a0438 ("dmaengine: break out channel registration")
Signed-off-by: Lv Yunlong <lyl2019@mail.ustc.edu.cn>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20210331014458.3944-1-lyl2019@mail.ustc.edu.cn
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The Xilinx dmaengine driver uses a tasklet to process completed
descriptors and execute their callbacks.
Currently consumers of the DMA channel have to no method of synchronization
against this tasklet when using the Xilinx dmaengine drivers. This can lead
to race conditions when the consumer frees resources that are accessed in
the callback before the tasklet has finished running.
It is not enough to just call dmaengine_terminal_all() since on a
multi-processor system the tasklet can run concurrently to it and might
call the callback after dmaengine_terminate_all() has already finished.
To mitigate this issue implement the synchronize() callback for the driver,
which will wait until the tasklet has finished.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Link: https://lore.kernel.org/r/20210313125311.4823-1-lars@metafoo.de
Signed-off-by: Vinod Koul <vkoul@kernel.org>
