linux.git/drivers/dma/idxd/cdev.c, branch v6.8

dmaengine: idxd: Remove shadow Event Log head stored in idxd

2024-02-16T12:16:56+00:00

head is defined in idxd->evl as a shadow of head in the EVLSTATUS register.
There are two issues related to the shadow head:

1. Mismatch between the shadow head and the state of the EVLSTATUS
   register:
   If Event Log is supported, upon completion of the Enable Device command,
   the Event Log head in the variable idxd->evl->head should be cleared to
   match the state of the EVLSTATUS register. But the variable is not reset
   currently, leading mismatch between the variable and the register state.
   The mismatch causes incorrect processing of Event Log entries.

2. Unnecessary shadow head definition:
   The shadow head is unnecessary as head can be read directly from the
   EVLSTATUS register. Reading head from the register incurs no additional
   cost because event log head and tail are always read together and
   tail is already read directly from the register as required by hardware.

Remove the shadow Event Log head stored in idxd->evl to address the
mentioned issues.

Fixes: 244da66cda35 ("dmaengine: idxd: setup event log configuration")
Signed-off-by: Fenghua Yu 
Reviewed-by: Dave Jiang 
Link: https://lore.kernel.org/r/20240215024931.1739621-1-fenghua.yu@intel.com
Signed-off-by: Vinod Koul

Merge tag 'dmaengine-fix-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine

2024-01-20T23:03:25+00:00

Pull dmaengine updates from Vinod Koul:
 "New support:
   - Loongson LS2X APB DMA controller
   - sf-pdma: mpfs-pdma support
   - Qualcomm X1E80100 GPI dma controller support

  Updates:
   - Xilinx XDMA updates to support interleaved DMA transfers
   - TI PSIL threads for AM62P and J722S and cfg register regions
     description
   - axi-dmac Improving the cyclic DMA transfers
   - Tegra Support dma-channel-mask property
   - Remaining platform remove callback returning void conversions

 Driver fixes for:
   - Xilinx xdma driver operator precedence and initialization fix
   - Excess kernel-doc warning fix in imx-sdma xilinx xdma drivers
   - format-overflow warning fix for rz-dmac, sh usb dmac drivers
   - 'output may be truncated' fix for shdma, fsl-qdma and dw-edma
     drivers"

* tag 'dmaengine-fix-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine: (58 commits)
  dmaengine: dw-edma: increase size of 'name' in debugfs code
  dmaengine: fsl-qdma: increase size of 'irq_name'
  dmaengine: shdma: increase size of 'dev_id'
  dmaengine: xilinx: xdma: Fix kernel-doc warnings
  dmaengine: usb-dmac: Avoid format-overflow warning
  dmaengine: sh: rz-dmac: Avoid format-overflow warning
  dmaengine: imx-sdma: fix Excess kernel-doc warnings
  dmaengine: xilinx: xdma: Fix initialization location of desc in xdma_channel_isr()
  dmaengine: xilinx: xdma: Fix operator precedence in xdma_prep_interleaved_dma()
  dmaengine: xilinx: xdma: statify xdma_prep_interleaved_dma
  dmaengine: xilinx: xdma: Workaround truncation compilation error
  dmaengine: pl330: issue_pending waits until WFP state
  dmaengine: xilinx: xdma: Implement interleaved DMA transfers
  dmaengine: xilinx: xdma: Prepare the introduction of interleaved DMA transfers
  dmaengine: xilinx: xdma: Add transfer error reporting
  dmaengine: xilinx: xdma: Add error checking in xdma_channel_isr()
  dmaengine: xilinx: xdma: Rework xdma_terminate_all()
  dmaengine: xilinx: xdma: Ease dma_pool alignment requirements
  dmaengine: xilinx: xdma: Add necessary macro definitions
  dmaengine: xilinx: xdma: Get rid of unused code
  ...

dmaengine: idxd: Remove usage of the deprecated ida_simple_xx() API

2023-12-21T15:59:21+00:00

ida_alloc() and ida_free() should be preferred to the deprecated
ida_simple_get() and ida_simple_remove().

This is less verbose.

Note that the upper limit of ida_simple_get() is exclusive, but the one of
ida_alloc_range() is inclusive. Sothis change allows one more device.

MINORMASK is ((1U << MINORBITS) - 1), so allowing MINORMASK as a maximum value
makes sense. It is also consistent with other "ida_.*MINORMASK" and
"ida_*MINOR()" usages.

Signed-off-by: Christophe JAILLET 
Reviewed-by: Fenghua Yu 
Acked-by: Lijun Pan 
Link: https://lore.kernel.org/r/ac991f5f42112fa782a881d391d447529cbc4a23.1702967302.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Vinod Koul

dmaengine: idxd: Rename drv_enable/disable_wq to idxd_drv_enable/disable_wq, and export

2023-12-15T09:52:53+00:00

Rename drv_enable_wq and drv_disable_wq to idxd_drv_enable_wq and
idxd_drv_disable_wq respectively, so that they're no longer too
generic to be exported.  This also matches existing naming within the
idxd driver.

And to allow idxd sub-drivers to enable and disable wqs, export them.

Signed-off-by: Tom Zanussi 
Reviewed-by: Dave Jiang 
Reviewed-by: Fenghua Yu 
Acked-by: Vinod Koul 
Signed-off-by: Herbert Xu

dmaengine: idxd: add wq driver name support for accel-config user tool

2023-10-04T07:30:34+00:00

With the possibility of multiple wq drivers that can be bound to the wq,
the user config tool accel-config needs a way to know which wq driver to
bind to the wq. Introduce per wq driver_name sysfs attribute where the user
can indicate the driver to be bound to the wq. This allows accel-config to
just bind to the driver using wq->driver_name.

Signed-off-by: Dave Jiang 
Signed-off-by: Tom Zanussi 
Reviewed-by: Fenghua Yu 
Acked-by: Vinod Koul 
Link: https://lore.kernel.org/r/20230908201045.4115614-1-fenghua.yu@intel.com
Signed-off-by: Vinod Koul

dmaengine: idxd: Fix passing freed memory in idxd_cdev_open()

2023-05-17T06:45:09+00:00

Smatch warns:
	drivers/dma/idxd/cdev.c:327:
		idxd_cdev_open() warn: 'sva' was already freed.

When idxd_wq_set_pasid() fails, the current code unbinds sva and then
goes to 'failed_set_pasid' where iommu_sva_unbind_device is called
again causing the above warning.
[ device_user_pasid_enabled(idxd) is still true when calling
failed_set_pasid ]

Fix this by removing additional unbind when idxd_wq_set_pasid() fails

Fixes: b022f59725f0 ("dmaengine: idxd: add idxd_copy_cr() to copy user completion record during page fault handling")
Signed-off-by: Harshit Mogalapalli 
Acked-by: Fenghua Yu 
Acked-by: Dave Jiang 
Link: https://lore.kernel.org/r/20230509060716.2830630-1-harshit.m.mogalapalli@oracle.com
Signed-off-by: Vinod Koul

dmaengine: idxd: add pid to exported sysfs attribute for opened file

2023-04-12T17:48:46+00:00

Provide the pid of the application for the opened file. This allows the
monitor daemon to easily correlate which app opened the file and easily
kill the app by pid if that is desired action.

Tested-by: Tony Zhu 
Signed-off-by: Dave Jiang 
Co-developed-by: Fenghua Yu 
Signed-off-by: Fenghua Yu 
Link: https://lore.kernel.org/r/20230407203143.2189681-16-fenghua.yu@intel.com
Signed-off-by: Vinod Koul

dmaengine: idxd: expose fault counters to sysfs

2023-04-12T17:48:46+00:00

Expose cr_faults and cr_fault_failures counters to the user space. This
allows a user app to keep track of how many fault the application is
causing with the completion record (CR) and also the number of failures
of the CR writeback. Having a high number of cr_fault_failures is bad as
the app is submitting descriptors with the CR addresses that are bad. User
monitoring daemon may want to consider killing the application as it may be
malicious and attempting to flood the device event log.

Tested-by: Tony Zhu 
Signed-off-by: Dave Jiang 
Co-developed-by: Fenghua Yu 
Signed-off-by: Fenghua Yu 
Link: https://lore.kernel.org/r/20230407203143.2189681-15-fenghua.yu@intel.com
Signed-off-by: Vinod Koul

dmaengine: idxd: add a device to represent the file opened

2023-04-12T17:48:45+00:00

Embed a struct device for the user file context in order to export sysfs
attributes related with the opened file. Tie the lifetime of the file
context to the device. The sysfs entry will be added under the char device.

Tested-by: Tony Zhu 
Signed-off-by: Dave Jiang 
Co-developed-by: Fenghua Yu 
Signed-off-by: Fenghua Yu 
Link: https://lore.kernel.org/r/20230407203143.2189681-14-fenghua.yu@intel.com
Signed-off-by: Vinod Koul

dmaengine: idxd: add per file user counters for completion record faults

2023-04-12T17:48:45+00:00

Add counters per opened file for the char device in order to keep track how
many completion record faults occurred and how many of those faults failed
the writeback by the driver after attempt to fault in the page. The
counters are managed by xarray that associates the PASID with
struct idxd_user_context.

Tested-by: Tony Zhu 
Signed-off-by: Dave Jiang 
Co-developed-by: Fenghua Yu 
Signed-off-by: Fenghua Yu 
Link: https://lore.kernel.org/r/20230407203143.2189681-13-fenghua.yu@intel.com
Signed-off-by: Vinod Koul