Commit Graph

17 Commits

Author SHA1 Message Date
Dan Williams 48667f6761 cxl/core: Split decoder setup into alloc + add
The kbuild robot reports:

    drivers/cxl/core/bus.c:516:1: warning: stack frame size (1032) exceeds
    limit (1024) in function 'devm_cxl_add_decoder'

It is also the case the devm_cxl_add_decoder() is unwieldy to use for
all the different decoder types. Fix the stack usage by splitting the
creation into alloc and add steps. This also allows for context
specific construction before adding.

With the split the caller is responsible for registering a devm callback
to trigger device_unregister() for the decoder rather than it being
implicit in the decoder registration. I.e. the routine that calls alloc
is responsible for calling put_device() if the "add" operation fails.

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Nathan Chancellor <nathan@kernel.org>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Ben Widawsky <ben.widawsky@intel.com>
Link: https://lore.kernel.org/r/163225205828.3038145.6831131648369404859.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-09-21 14:09:34 -07:00
Dan Williams 7d3eb23c4c tools/testing/cxl: Introduce a mock memory device + driver
Introduce an emulated device-set plus driver to register CXL memory
devices, 'struct cxl_memdev' instances, in the mock cxl_test topology.
This enables the development of HDM Decoder (Host-managed Device Memory
Decoder) programming flow (region provisioning) in an environment that
can be updated alongside the kernel as it gains more functionality.

Whereas the cxl_pci module looks for CXL memory expanders on the 'pci'
bus, the cxl_mock_mem module attaches to CXL expanders on the platform
bus emitted by cxl_test.

Acked-by: Ben Widawsky <ben.widawsky@intel.com>
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/163116440099.2460985.10692549614409346604.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-09-21 14:09:34 -07:00
Dan Williams 49be6dd807 cxl/mbox: Move command definitions to common location
In preparation for cxl_test to mock responses to mailbox command
requests, move some definitions from core/mbox.c to cxlmem.h.

No functional changes intended.

Acked-by: Ben Widawsky <ben.widawsky@intel.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/163116439547.2460985.10457111177103589574.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-09-21 14:09:34 -07:00
Dan Williams a5c2580216 cxl/bus: Populate the target list at decoder create
As found by cxl_test, the implementation populated the target_list for
the single dport exceptional case, it missed populating the target_list
for the typical multi-dport case. Root decoders always know their target
list at the beginning of time, and even switch-level decoders should
have a target list of one or more zeros by default, depending on the
interleave-ways setting.

Walk the hosting port's dport list and populate based on the passed in
map.

Move devm_cxl_add_passthrough_decoder() out of line now that it does the
work of generating a target_map.

Before:
$ cat /sys/bus/cxl/devices/root2/decoder*/target_list
0

0

After:
$ cat /sys/bus/cxl/devices/root2/decoder*/target_list
0
0,1,2,3
0
0,1,2,3

Where root2 is a CXL topology root object generated by 'cxl_test'.

Acked-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/163116439000.2460985.11713777051267946018.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-09-21 14:09:34 -07:00
Dan Williams 2e52b6256b cxl/pmem: Add support for multiple nvdimm-bridge objects
In preparation for a mocked unit test environment for CXL objects, allow
for multiple unique nvdimm-bridge objects.

For now, just allow multiple bridges to be registered. Later, when there
are multiple present, further updates are needed to
cxl_find_nvdimm_bridge() to identify which bridge is associated with
which CXL hierarchy for nvdimm registration.

Note that this does change the kernel device-name for the bridge object.
User space should not have any attachment to the device name at this
point as it is still early days in the CXL driver development.

Acked-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/163164647007.2831228.2150246954620721526.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-09-21 13:47:10 -07:00
Dan Williams 12f3856ad4 cxl/mbox: Add exclusive kernel command support
The CXL_PMEM driver expects exclusive control of the label storage area
space. Similar to the LIBNVDIMM expectation that the label storage area
is only writable from userspace when the corresponding memory device is
not active in any region, the expectation is the native CXL_PCI UAPI
path is disabled while the cxl_nvdimm for a given cxl_memdev device is
active in LIBNVDIMM.

Add the ability to toggle the availability of a given command for the
UAPI path. Use that new capability to shutdown changes to partitions and
the label storage area while the cxl_nvdimm device is actively proxying
commands for LIBNVDIMM.

Reviewed-by: Ben Widawsky <ben.widawsky@intel.com>
Link: https://lore.kernel.org/r/163164579468.2830966.6980053377428474263.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-09-21 13:44:57 -07:00
Dan Williams ff56ab9e16 cxl/mbox: Convert 'enabled_cmds' to DECLARE_BITMAP
Define enabled_cmds as an embedded member of 'struct cxl_mem' rather
than a pointer to another dynamic allocation.

As this leaves only one user of cxl_cmd_count, just open code it and
delete the helper.

Acked-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/163116436415.2460985.10101824045493194813.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-09-21 13:44:57 -07:00
Dan Williams 4faf31b434 cxl/mbox: Move mailbox and other non-PCI specific infrastructure to the core
Now that the internals of mailbox operations are abstracted from the PCI
specifics a bulk of infrastructure can move to the core.

The CXL_PMEM driver intends to proxy LIBNVDIMM UAPI and driver requests
to the equivalent functionality provided by the CXL hardware mailbox
interface. In support of that intent move the mailbox implementation to
a shared location for the CXL_PCI driver native IOCTL path and CXL_PMEM
nvdimm command proxy path to share.

A unit test framework seeks to implement a unit test backend transport
for mailbox commands to communicate mocked up payloads. It can reuse all
of the mailbox infrastructure minus the PCI specifics, so that also gets
moved to the core.

Finally with the mailbox infrastructure and ioctl handling being
transport generic there is no longer any need to pass file
file_operations to devm_cxl_add_memdev(). That allows all the ioctl
boilerplate to move into the core for unit test reuse.

No functional change intended, just code movement.

Acked-by: Ben Widawsky <ben.widawsky@intel.com>
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/163116435233.2460985.16197340449713287180.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-09-21 13:44:56 -07:00
Dan Williams 99e222a5f1 cxl/pci: Make 'struct cxl_mem' device type generic
In preparation for adding a unit test provider of a cxl_memdev, convert
the 'struct cxl_mem' driver context to carry a generic device rather
than a pci device.

Note, some dev_dbg() lines needed extra reformatting per clang-format.

This conversion also allows the cxl_mem_create() and
devm_cxl_add_memdev() calling conventions to be simplified. The "host"
for a cxl_memdev, must be the same device for the driver that allocated
@cxlm.

Acked-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Ben Widawsky <ben.widawsky@intel.com>
Link: https://lore.kernel.org/r/163116432973.2460985.7553504957932024222.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-09-21 13:44:56 -07:00
Linus Torvalds 70868a1805 cxl for v5.15
- Fix detection of CXL host bridges to filter out disabled ACPI0016
   devices in the ACPI DSDT.
 
 - Fix kernel lockdown integration to disable raw commands when raw PCI
   access is disabled.
 
 - Fix a broken debug message.
 
 - Add support for "Get Partition Info". I.e. enumerate the split between
   volatile and persistent capacity on bi-modal CXL memory expanders.
 
 - Re-factor the core by subject area. This is a work in progress.
 
 - Prepare libnvdimm to understand CXL labels in addition to EFI labels.
   This is a work in progress.
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Merge tag 'cxl-for-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl

Pull CXL (Compute Express Link) updates from Dan Williams:

 - Fix detection of CXL host bridges to filter out disabled ACPI0016
   devices in the ACPI DSDT.

 - Fix kernel lockdown integration to disable raw commands when raw PCI
   access is disabled.

 - Fix a broken debug message.

 - Add support for "Get Partition Info". I.e. enumerate the split
   between volatile and persistent capacity on bi-modal CXL memory
   expanders.

 - Re-factor the core by subject area. This is a work in progress.

 - Prepare libnvdimm to understand CXL labels in addition to EFI labels.
   This is a work in progress.

* tag 'cxl-for-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl: (25 commits)
  cxl/registers: Fix Documentation warning
  cxl/pmem: Fix Documentation warning
  cxl/uapi: Fix defined but not used warnings
  cxl/pci: Fix debug message in cxl_probe_regs()
  cxl/pci: Fix lockdown level
  cxl/acpi: Do not add DSDT disabled ACPI0016 host bridge ports
  libnvdimm/labels: Add claim class helpers
  libnvdimm/labels: Add type-guid helpers
  libnvdimm/labels: Add blk special cases for nlabel and position helpers
  libnvdimm/labels: Add blk isetcookie set / validation helpers
  libnvdimm/labels: Add a checksum calculation helper
  libnvdimm/labels: Introduce label setter helpers
  libnvdimm/labels: Add isetcookie validation helper
  libnvdimm/labels: Introduce getters for namespace label fields
  cxl/mem: Adjust ram/pmem range to represent DPA ranges
  cxl/mem: Account for partitionable space in ram/pmem ranges
  cxl/pci: Store memory capacity values
  cxl/pci: Simplify register setup
  cxl/pci: Ignore unknown register block types
  cxl/core: Move memdev management to core
  ...
2021-09-09 11:48:27 -07:00
Dan Williams 2b922a9d06 cxl/registers: Fix Documentation warning
Commit 0f06157e01 ("cxl/core: Move register mapping infrastructure")
neglected to add a DOC header for the new drivers/core/regs.c file.

Reported-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/163072206675.2250120.3527179192933919995.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-09-07 11:39:02 -07:00
Dan Williams a01da6ca7d cxl/pmem: Fix Documentation warning
Commit 06737cd0d2 ("cxl/core: Move pmem functionality") neglected to
add a DOC header for the new drivers/cxl/core/pmem.c file.

Reported-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huwei.com>
Link: https://lore.kernel.org/r/163072206163.2250120.11486436976516079516.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-09-07 11:39:01 -07:00
Ben Widawsky 3d135db510 cxl/core: Move memdev management to core
The motivation for moving cxl_memdev allocation to the core (beyond
better file organization of sysfs attributes in core/ and drivers in
cxl/), is that device lifetime is longer than module lifetime. The cxl_pci
module should be free to come and go without needing to coordinate with
devices that need the text associated with cxl_memdev_release() to stay
resident. The move fixes a use after free bug when looping driver
load / unload with CONFIG_DEBUG_KOBJECT_RELEASE=y.

Another motivation for disconnecting cxl_memdev creation from cxl_pci is
to enable other drivers, like a unit test driver, to registers memdevs.

Fixes: b39cb1052a ("cxl/mem: Register CXL memX devices")
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/162792540495.368511.9748638751088219595.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-08-06 08:22:54 -07:00
Dan Williams 0f06157e01 cxl/core: Move register mapping infrastructure
The register mapping infrastructure is large enough to move to its own
compilation unit. This also cleans up an unnecessary include of <mem.h>
core/bus.c.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/162800068975.665205.12895551621746585289.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-08-06 08:22:53 -07:00
Dan Williams 06737cd0d2 cxl/core: Move pmem functionality
Refactor the pmem / nvdimm-bridge functionality from core/bus.c to
core/pmem.c. Introduce drivers/core/core.h to communicate data
structures and helpers between the core bus and other functionality that
registers devices on the bus.

Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/162792538899.368511.3881663908293411300.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-08-06 08:22:53 -07:00
Ben Widawsky 95aaed2668 cxl/core: Improve CXL core kernel docs
Now that CXL core's role is well understood, the documentation should
reflect that information.

Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/162792538379.368511.9055351193841619781.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-08-06 08:22:53 -07:00
Ben Widawsky 5161a55c06 cxl: Move cxl_core to new directory
CXL core is growing, and it's already arguably unmanageable. To support
future growth, move core functionality to a new directory and rename the
file to represent just bus support. Future work will remove non-bus
functionality.

Note that mem.h is renamed to cxlmem.h to avoid a namespace collision
with the global ARCH=um mem.h header.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/162792537866.368511.8915631504621088321.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2021-08-06 08:22:53 -07:00