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path: root/drivers/cxl/core/memdev.c
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2025-03-17Merge branch 'for-6.15/features' into cxl-for-nextDave Jiang
Add CXL Features support. Setup code for enabling in kernel usage of CXL Features. Expecting EDAC/RAS to utilize CXL Features in kernel for things such as memory sparing. Also prepartion for enabling of CXL FWCTL support to issue allowed Features from user space.
2025-03-14Merge branch 'for-6.15/guard_cleanups' into cxl-for-next2Dave Jiang
A series of CXL refactoring using scope based resource management to remove goto patterns on the cleanup paths.
2025-03-14cxl/memdev: cxl_memdev_ioctl() cleanupLi Ming
In cxl_memdev_ioctl(), the down_read(&cxl_memdev_rwsem) and up_read(&cxl_memdev_rwsem) can be replaced by a guard(rwsem_read)(&cxl_memdev_rwsem), it helps to remove the open-coded up_read(&cxl_memdev_rwsem). Besides, the local var 'rc' can be also removed to make the code more cleaner. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Acked-by: Davidlohr Bueso <dave@stgolabs.net> Signed-off-by: Li Ming <ming.li@zohomail.com> Link: https://patch.msgid.link/20250221012453.126366-4-ming.li@zohomail.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2025-03-14cxl/core: Use guard() to replace open-coded down_read/write()Li Ming
Some down/up_read() and down/up_write() cases can be replaced by a guard() simply to drop explicit unlock invoked. It helps to align coding style with current CXL subsystem's. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Acked-by: Davidlohr Bueso <dave@stgolabs.net> Signed-off-by: Li Ming <ming.li@zohomail.com> Link: https://patch.msgid.link/20250221012453.126366-2-ming.li@zohomail.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2025-02-24cxl: Refactor user ioctl command path from mds to mailboxDave Jiang
With 'struct cxl_mailbox' context introduced, the helper functions cxl_query_cmd() and cxl_send_cmd() can take a cxl_mailbox directly rather than a cxl_memdev parameter. Refactor to use cxl_mailbox directly. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Link: https://patch.msgid.link/20250204220430.4146187-2-dave.jiang@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2025-02-04cxl: Cleanup partition size and perf helpersDan Williams
Now that the 'struct cxl_dpa_partition' array contains both size and performance information, all paths that iterate over that information can use a loop rather than hard-code 'ram' and 'pmem' lookups. Remove, or reduce the scope of the temporary helpers that bridged the pre-'struct cxl_dpa_partition' state of the code to the post-'struct cxl_dpa_partition' state. - to_{ram,pmem}_perf(): scope reduced to just sysfs_emit + is_visible() helpers - to_{ram,pmem}_res(): fold into their only users cxl_{ram,pmem}_size() - cxl_ram_size(): scope reduced to ram_size_show() (Note, cxl_pmem_size() also used to gate nvdimm registration) In short, memdev sysfs ABI already made the promise that 0-sized partitions will show for memdevs, but that can be avoided for future partitions by using dynamic sysfs group visibility (new relative to when the partition ABI first shipped upstream). Cc: Dave Jiang <dave.jiang@intel.com> Cc: Alejandro Lucero <alucerop@amd.com> Cc: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Tested-by: Alejandro Lucero <alucerop@amd.com> Link: https://patch.msgid.link/173864307519.668823.10800104022426067621.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2025-02-04cxl: Kill enum cxl_decoder_modeDan Williams
Now that the operational mode of DPA capacity (ram vs pmem... etc) is tracked in the partition, and no code paths have dependencies on the mode implying the partition index, the ambiguous 'enum cxl_decoder_mode' can be cleaned up, specifically this ambiguity on whether the operation mode implied anything about the partition order. Endpoint decoders simply reference their assigned partition where the operational mode can be retrieved as partition mode. With this in place PMEM can now be partition0 which happens today when the RAM capacity size is zero. Dynamic RAM can appear above PMEM when DCD arrives, etc. Code sequences that hard coded the "PMEM after RAM" assumption can now just iterate partitions and consult the partition mode after the fact. Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Alejandro Lucero <alucerop@amd.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Tested-by: Alejandro Lucero <alucerop@amd.com> Link: https://patch.msgid.link/173864306972.668823.3327008645125276726.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2025-02-04cxl: Introduce 'struct cxl_dpa_partition' and 'struct cxl_range_info'Dan Williams
The pending efforts to add CXL Accelerator (type-2) device [1], and Dynamic Capacity (DCD) support [2], tripped on the no-longer-fit-for-purpose design in the CXL subsystem for tracking device-physical-address (DPA) metadata. Trip hazards include: - CXL Memory Devices need to consider a PMEM partition, but Accelerator devices with CXL.mem likely do not in the common case. - CXL Memory Devices enumerate DPA through Memory Device mailbox commands like Partition Info, Accelerators devices do not. - CXL Memory Devices that support DCD support more than 2 partitions. Some of the driver algorithms are awkward to expand to > 2 partition cases. - DPA performance data is a general capability that can be shared with accelerators, so tracking it in 'struct cxl_memdev_state' is no longer suitable. - Hardcoded assumptions around the PMEM partition always being index-1 if RAM is zero-sized or PMEM is zero sized. - 'enum cxl_decoder_mode' is sometimes a partition id and sometimes a memory property, it should be phased in favor of a partition id and the memory property comes from the partition info. Towards cleaning up those issues and allowing a smoother landing for the aforementioned pending efforts, introduce a 'struct cxl_dpa_partition' array to 'struct cxl_dev_state', and 'struct cxl_range_info' as a shared way for Memory Devices and Accelerators to initialize the DPA information in 'struct cxl_dev_state'. For now, split a new cxl_dpa_setup() from cxl_mem_create_range_info() to get the new data structure initialized, and cleanup some qos_class init. Follow on patches will go further to use the new data structure to cleanup algorithms that are better suited to loop over all possible partitions. cxl_dpa_setup() follows the locking expectations of mutating the device DPA map, and is suitable for Accelerator drivers to use. Accelerators likely only have one hardcoded 'ram' partition to convey to the cxl_core. Link: http://lore.kernel.org/20241230214445.27602-1-alejandro.lucero-palau@amd.com [1] Link: http://lore.kernel.org/20241210-dcd-type2-upstream-v8-0-812852504400@intel.com [2] Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Alejandro Lucero <alucerop@amd.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Tested-by: Alejandro Lucero <alucerop@amd.com> Link: https://patch.msgid.link/173864305827.668823.13978794102080021276.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2025-02-04cxl: Introduce to_{ram,pmem}_{res,perf}() helpersDan Williams
In preparation for consolidating all DPA partition information into an array of DPA metadata, introduce helpers that hide the layout of the current data. I.e. make the eventual replacement of ->ram_res, ->pmem_res, ->ram_perf, and ->pmem_perf with a new DPA metadata array a no-op for code paths that consume that information, and reduce the noise of follow-on patches. The end goal is to consolidate all DPA information in 'struct cxl_dev_state', but for now the helpers just make it appear that all DPA metadata is relative to @cxlds. As the conversion to generic partition metadata walking is completed, these helpers will naturally be eliminated, or reduced in scope. Cc: Alejandro Lucero <alucerop@amd.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Fan Ni <fan.ni@samsung.com> Tested-by: Alejandro Lucero <alucerop@amd.com> Link: https://patch.msgid.link/173864305238.668823.16553986866633608541.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-12-02module: Convert symbol namespace to string literalPeter Zijlstra
Clean up the existing export namespace code along the same lines of commit 33def8498fdd ("treewide: Convert macro and uses of __section(foo) to __section("foo")") and for the same reason, it is not desired for the namespace argument to be a macro expansion itself. Scripted using git grep -l -e MODULE_IMPORT_NS -e EXPORT_SYMBOL_NS | while read file; do awk -i inplace ' /^#define EXPORT_SYMBOL_NS/ { gsub(/__stringify\(ns\)/, "ns"); print; next; } /^#define MODULE_IMPORT_NS/ { gsub(/__stringify\(ns\)/, "ns"); print; next; } /MODULE_IMPORT_NS/ { $0 = gensub(/MODULE_IMPORT_NS\(([^)]*)\)/, "MODULE_IMPORT_NS(\"\\1\")", "g"); } /EXPORT_SYMBOL_NS/ { if ($0 ~ /(EXPORT_SYMBOL_NS[^(]*)\(([^,]+),/) { if ($0 !~ /(EXPORT_SYMBOL_NS[^(]*)\(([^,]+), ([^)]+)\)/ && $0 !~ /(EXPORT_SYMBOL_NS[^(]*)\(\)/ && $0 !~ /^my/) { getline line; gsub(/[[:space:]]*\\$/, ""); gsub(/[[:space:]]/, "", line); $0 = $0 " " line; } $0 = gensub(/(EXPORT_SYMBOL_NS[^(]*)\(([^,]+), ([^)]+)\)/, "\\1(\\2, \"\\3\")", "g"); } } { print }' $file; done Requested-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://mail.google.com/mail/u/2/#inbox/FMfcgzQXKWgMmjdFwwdsfgxzKpVHWPlc Acked-by: Greg KH <gregkh@linuxfoundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2024-09-12cxl: Convert cxl_internal_send_cmd() to use 'struct cxl_mailbox' as inputDave Jiang
With the CXL mailbox context split out, cxl_internal_send_cmd() can take 'struct cxl_mailbox' as an input parameter rather than 'struct memdev_dev_state'. Change input parameter for cxl_internal_send_cmd() and fixup all impacted call sites. Reviewed-by: Fan Ni <fan.ni@samsung.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://patch.msgid.link/20240905223711.1990186-4-dave.jiang@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-09-12cxl: Move mailbox related bits to the same contextDave Jiang
Create a new 'struct cxl_mailbox' and move all mailbox related bits to it. This allows isolation of all CXL mailbox data in order to export some of the calls to external kernel callers and avoid exporting of CXL driver specific bits such has device states. The allocation of 'struct cxl_mailbox' is also split out with cxl_mailbox_init() so the mailbox can be created independently. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Alejandro Lucero <alucerop@amd.com> Reviewed-by: Fan Ni <fan.ni@samsung.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://patch.msgid.link/20240905223711.1990186-3-dave.jiang@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-04-30cxl/region: Move cxl_dpa_to_region() work to the region driverAlison Schofield
This helper belongs in the region driver as it is only useful with CONFIG_CXL_REGION. Add a stub in core.h for when the region driver is not built. Signed-off-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/05e30f788d62b3dd398aff2d2ea50a6aaa7c3313.1714496730.git.alison.schofield@intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com>
2024-02-16cxl: Fix sysfs export of qos_class for memdevDave Jiang
Current implementation exports only to /sys/bus/cxl/devices/.../memN/qos_class. With both ram and pmem exposed, the second registered sysfs attribute is rejected as duplicate. It's not possible to create qos_class under the dev_groups via the driver due to the ram and pmem sysfs sub-directories already created by the device sysfs groups. Move the ram and pmem qos_class to the device sysfs groups and add a call to sysfs_update() after the perf data are validated so the qos_class can be visible. The end results should be /sys/bus/cxl/devices/.../memN/ram/qos_class and /sys/bus/cxl/devices/.../memN/pmem/qos_class. Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/20240206190431.1810289-4-dave.jiang@intel.com Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2024-01-12cxl/core: use sysfs_emit() for attr's _show()Shiyang Ruan
sprintf() is deprecated for sysfs, use preferred sysfs_emit() instead. Signed-off-by: Shiyang Ruan <ruansy.fnst@fujitsu.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Fan Ni <fan.ni@samsung.com> Link: https://lore.kernel.org/r/20240112062709.2490947-1-ruansy.fnst@fujitsu.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-11-29cxl/memdev: Hold region_rwsem during inject and clear poison opsAlison Schofield
Poison inject and clear are supported via debugfs where a privileged user can inject and clear poison to a device physical address. Commit 458ba8189cb4 ("cxl: Add cxl_decoders_committed() helper") added a lockdep assert that highlighted a gap in poison inject and clear functions where holding the dpa_rwsem does not assure that a a DPA is not added to a region. The impact for inject and clear is that if the DPA address being injected or cleared has been attached to a region, but not yet committed, the dev_dbg() message intended to alert the debug user that they are acting on a mapped address is not emitted. Also, the cxl_poison trace event that serves as a log of the inject and clear activity will not include region info. Close this gap by snapshotting an unchangeable region state during poison inject and clear operations. That means holding both the region_rwsem and the dpa_rwsem during the inject and clear ops. Fixes: d2fbc4865802 ("cxl/memdev: Add support for the Inject Poison mailbox command") Fixes: 9690b07748d1 ("cxl/memdev: Add support for the Clear Poison mailbox command") Signed-off-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Davidlohr Bueso <dave@stgolabs.net> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/08721dc1df0a51e4e38fecd02425c3475912dfd5.1701041440.git.alison.schofield@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-11-29cxl/core: Always hold region_rwsem while reading poison listsAlison Schofield
A read of a device poison list is triggered via a sysfs attribute and the results are logged as kernel trace events of type cxl_poison. The work is managed by either: a) the region driver when one of more regions map the device, or by b) the memdev driver when no regions map the device. In the case of a) the region driver holds the region_rwsem while reading the poison by committed endpoint decoder mappings and for any unmapped resources. This makes sure that the cxl_poison trace event trace reports valid region info. (Region name, HPA, and UUID). In the case of b) the memdev driver holds the dpa_rwsem preventing new DPA resources from being attached to a region. However, it leaves a gap between region attach and decoder commit actions. If a DPA in the gap is in the poison list, the cxl_poison trace event will omit the region info. Close the gap by holding the region_rwsem and the dpa_rwsem when reading poison per memdev. Since both methods now hold both locks, down_read both from the caller. Doing so also addresses the lockdep assert that found this issue: Commit 458ba8189cb4 ("cxl: Add cxl_decoders_committed() helper") Fixes: f0832a586396 ("cxl/region: Provide region info to the cxl_poison trace event") Signed-off-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Davidlohr Bueso <dave@stgolabs.net> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/08e8e7ec9a3413b91d51de39e385653494b1eed0.1701041440.git.alison.schofield@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-10-27cxl: Add cxl_decoders_committed() helperDave Jiang
Add a helper to retrieve the number of decoders committed for the port. Replace all the open coding of the calculation with the helper. Link: https://lore.kernel.org/linux-cxl/651c98472dfed_ae7e729495@dwillia2-xfh.jf.intel.com.notmuch/ Suggested-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Jim Harris <jim.harris@samsung.com> Reviewed-by: Alison Schofield <alison.schofield@intel.com> Link: https://lore.kernel.org/r/169747906849.272156.1729290904857372335.stgit@djiang5-mobl3 Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-10-09cxl/mem: Fix shutdown orderDan Williams
Ira reports that removing cxl_mock_mem causes a crash with the following trace: BUG: kernel NULL pointer dereference, address: 0000000000000044 [..] RIP: 0010:cxl_region_decode_reset+0x7f/0x180 [cxl_core] [..] Call Trace: <TASK> cxl_region_detach+0xe8/0x210 [cxl_core] cxl_decoder_kill_region+0x27/0x40 [cxl_core] cxld_unregister+0x29/0x40 [cxl_core] devres_release_all+0xb8/0x110 device_unbind_cleanup+0xe/0x70 device_release_driver_internal+0x1d2/0x210 bus_remove_device+0xd7/0x150 device_del+0x155/0x3e0 device_unregister+0x13/0x60 devm_release_action+0x4d/0x90 ? __pfx_unregister_port+0x10/0x10 [cxl_core] delete_endpoint+0x121/0x130 [cxl_core] devres_release_all+0xb8/0x110 device_unbind_cleanup+0xe/0x70 device_release_driver_internal+0x1d2/0x210 bus_remove_device+0xd7/0x150 device_del+0x155/0x3e0 ? lock_release+0x142/0x290 cdev_device_del+0x15/0x50 cxl_memdev_unregister+0x54/0x70 [cxl_core] This crash is due to the clearing out the cxl_memdev's driver context (@cxlds) before the subsystem is done with it. This is ultimately due to the region(s), that this memdev is a member, being torn down and expecting to be able to de-reference @cxlds, like here: static int cxl_region_decode_reset(struct cxl_region *cxlr, int count) ... if (cxlds->rcd) goto endpoint_reset; ... Fix it by keeping the driver context valid until memdev-device unregistration, and subsequently the entire stack of related dependencies, unwinds. Fixes: 9cc238c7a526 ("cxl/pci: Introduce cdevm_file_operations") Reported-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Davidlohr Bueso <dave@stgolabs.net> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Tested-by: Ira Weiny <ira.weiny@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-10-06cxl/memdev: Fix sanitize vs decoder setup lockingDan Williams
The sanitize operation is destructive and the expectation is that the device is unmapped while in progress. The current implementation does a lockless check for decoders being active, but then does nothing to prevent decoders from racing to be committed. Introduce state tracking to resolve this race. This incidentally cleans up unpriveleged userspace from triggering mmio read cycles by spinning on reading the 'security/state' attribute. Which at a minimum is a waste since the kernel state machine can cache the completion result. Lastly cxl_mem_sanitize() was mistakenly marked EXPORT_SYMBOL() in the original implementation, but an export was never required. Fixes: 0c36b6ad436a ("cxl/mbox: Add sanitization handling machinery") Cc: Davidlohr Bueso <dave@stgolabs.net> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Davidlohr Bueso <dave@stgolabs.net> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-10-06cxl/pci: Fix sanitize notifier setupDan Williams
Fix a race condition between the mailbox-background command interrupt firing and the security-state sysfs attribute being removed. The race is difficult to see due to the awkward placement of the sanitize-notifier setup code and the multiple places the teardown calls are made, cxl_memdev_security_init() and cxl_memdev_security_shutdown(). Unify setup in one place, cxl_sanitize_setup_notifier(). Arrange for the paired cxl_sanitize_teardown_notifier() to safely quiet the notifier and let the cxl_memdev + irq be unregistered later in the flow. Note: The special wrinkle of the sanitize notifier is that it interacts with interrupts, which are enabled early in the flow, and it interacts with memdev sysfs which is not initialized until late in the flow. Hence why this setup routine takes an @cxlmd argument, and not just @mds. This fix is also needed as a preparation fix for a memdev unregistration crash. Reported-by: Jonathan Cameron <Jonathan.Cameron@Huawei.com> Closes: http://lore.kernel.org/r/20230929100316.00004546@Huawei.com Cc: Dave Jiang <dave.jiang@intel.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Fixes: 0c36b6ad436a ("cxl/mbox: Add sanitization handling machinery") Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Davidlohr Bueso <dave@stgolabs.net> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-10-06cxl/pci: Clarify devm host for memdev relative setupDan Williams
It is all too easy to get confused about @dev usage in the CXL driver stack. Before adding a new cxl_pci_probe() setup operation that has a devm lifetime dependent on @cxlds->dev binding, but also references @cxlmd->dev, and prints messages, rework the devm_cxl_add_memdev() and cxl_memdev_setup_fw_upload() function signatures to make this distinction explicit. I.e. pass in the devm context as an @host argument rather than infer it from other objects. This is in preparation for adding a devm_cxl_sanitize_setup_notifier(). Note the whitespace fixup near the change of the devm_cxl_add_memdev() signature. That uncaught typo originated in the patch that added cxl_memdev_security_init(). Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-10-06cxl/pci: Remove inconsistent usage of dev_err_probe()Dan Williams
If dev_err_probe() is to be used it should at least be used consistently within the same function. It is also worth questioning whether every potential -ENOMEM needs an explicit error message. Remove the cxl_setup_fw_upload() error prints for what are rare / hardware-independent failures. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Davidlohr Bueso <dave@stgolabs.net> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-09-29cxl/pci: Cleanup 'sanitize' to always pollDan Williams
In preparation for fixing the init/teardown of the 'sanitize' workqueue and sysfs notification mechanism, arrange for cxl_mbox_sanitize_work() to be the single location where the sysfs attribute is notified. With that change there is no distinction between polled mode and interrupt mode. All the interrupt does is accelerate the polling interval. The change to check for "mds->security.sanitize_node" under the lock is there to ensure that the interrupt, the work routine and the setup/teardown code can all have a consistent view of the registered notifier and the workqueue state. I.e. the expectation is that the interrupt is live past the point that the sanitize sysfs attribute is published, and it may race teardown, so it must be consulted under a lock. Given that new locking requirement, cxl_pci_mbox_irq() is moved from hard to thread irq context. Lastly, some opportunistic replacements of "queue_delayed_work(system_wq, ...)", which is just open coded schedule_delayed_work(), are included. Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Davidlohr Bueso <dave@stgolabs.net> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-07-28cxl/memdev: Only show sanitize sysfs files when supportedDavidlohr Bueso
If the device does not support Sanitize or Secure Erase commands, hide the respective sysfs interfaces such that the operation can never be attempted. In order to be generic, keep track of the enabled security commands found in the CEL - the driver does not support Security Passthrough. Signed-off-by: Davidlohr Bueso <dave@stgolabs.net> Link: https://lore.kernel.org/r/20230726051940.3570-4-dave@stgolabs.net Reviewed-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
2023-06-29cxl: Fix one kernel-doc commentYang Li
Fix a merge error that updated the argument to cxl_mem_get_fw_info() but not the kernel-doc. drivers/cxl/core/memdev.c:678: warning: Function parameter or member 'mds' not described in 'cxl_mem_get_fw_info' drivers/cxl/core/memdev.c:678: warning: Excess function parameter 'cxlds' description in 'cxl_mem_get_fw_info' Signed-off-by: Yang Li <yang.lee@linux.alibaba.com> Link: https://lore.kernel.org/r/20230629021118.102744-1-yang.lee@linux.alibaba.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-06-25Merge branch 'for-6.5/cxl-type-2' into for-6.5/cxlDan Williams
Pick up the driver cleanups identified in preparation for CXL "type-2" (accelerator) device support. The major change here from a conflict generation perspective is the split of 'struct cxl_memdev_state' from the core 'struct cxl_dev_state'. Since an accelerator may not care about all the optional features that are standard on a CXL "type-3" (host-only memory expander) device. A silent conflict also occurs with the move of the endpoint port to be a formal property of a 'struct cxl_memdev' rather than drvdata.
2023-06-25Merge branch 'for-6.5/cxl-fwupd' into for-6.5/cxlDan Williams
Add the first typical (non-sanitization) consumer of the new background command infrastructure, firmware update. Given both firmware-update and sanitization were developed in parallel from the common background-command baseline, resolve some minor context conflicts.
2023-06-25cxl: add a firmware update mechanism using the sysfs firmware loaderVishal Verma
The sysfs based firmware loader mechanism was created to easily allow userspace to upload firmware images to FPGA cards. This also happens to be pretty suitable to create a user-initiated but kernel-controlled firmware update mechanism for CXL devices, using the CXL specified mailbox commands. Since firmware update commands can be long-running, and can be processed in the background by the endpoint device, it is desirable to have the ability to chunk the firmware transfer down to smaller pieces, so that one operation does not monopolize the mailbox, locking out any other long running background commands entirely - e.g. security commands like 'sanitize' or poison scanning operations. The firmware loader mechanism allows a natural way to perform this chunking, as after each mailbox command, that is restricted to the maximum mailbox payload size, the cxl memdev driver relinquishes control back to the fw_loader system and awaits the next chunk of data to transfer. This opens opportunities for other background commands to access the mailbox and send their own slices of background commands. Add the necessary helpers and state tracking to be able to perform the 'Get FW Info', 'Transfer FW', and 'Activate FW' mailbox commands as described in the CXL spec. Wire these up to the firmware loader callbacks, and register with that system to create the memX/firmware/ sysfs ABI. Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Jonathan Cameron <Jonathan.Cameron@Huawei.com> Cc: Russ Weight <russell.h.weight@intel.com> Cc: Alison Schofield <alison.schofield@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Ben Widawsky <bwidawsk@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Vishal Verma <vishal.l.verma@intel.com> Link: https://lore.kernel.org/r/20230602-vv-fw_update-v4-1-c6265bd7343b@intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-06-25cxl/mem: Support Secure EraseDavidlohr Bueso
Implement support for the non-pmem exclusive secure erase, per CXL specs. Create a write-only 'security/erase' sysfs file to perform the requested operation. As with the sanitation this requires the device being offline and thus no active HPA-DPA decoding. The expectation is that userspace can use it such as: cxl disable-memdev memX echo 1 > /sys/bus/cxl/devices/memX/security/erase cxl enable-memdev memX Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Fan Ni <fan.ni@samsung.com> Signed-off-by: Davidlohr Bueso <dave@stgolabs.net> Link: https://lore.kernel.org/r/20230612181038.14421-7-dave@stgolabs.net Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-06-25cxl/mem: Wire up Sanitization supportDavidlohr Bueso
Implement support for CXL 3.0 8.2.9.8.5.1 Sanitize. This is done by adding a security/sanitize' memdev sysfs file to trigger the operation and extend the status file to make it poll(2)-capable for completion. Unlike all other background commands, this is the only operation that is special and monopolizes the device for long periods of time. In addition to the traditional pmem security requirements, all regions must also be offline in order to perform the operation. This permits avoiding explicit global CPU cache management, relying instead on the implict cache management when a region transitions between CXL_CONFIG_ACTIVE and CXL_CONFIG_COMMIT. The expectation is that userspace can use it such as: cxl disable-memdev memX echo 1 > /sys/bus/cxl/devices/memX/security/sanitize cxl wait-sanitize memX cxl enable-memdev memX Reviewed-by: Dave Jiang <dave.jiang@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Davidlohr Bueso <dave@stgolabs.net> Link: https://lore.kernel.org/r/20230612181038.14421-5-dave@stgolabs.net Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-06-25cxl/mbox: Add sanitization handling machineryDavidlohr Bueso
Sanitization is by definition a device-monopolizing operation, and thus the timeslicing rules for other background commands do not apply. As such handle this special case asynchronously and return immediately. Subsequent changes will allow completion to be pollable from userspace via a sysfs file interface. For devices that don't support interrupts for notifying background command completion, self-poll with the caveat that the poller can be out of sync with the ready hardware, and therefore care must be taken to not allow any new commands to go through until the poller sees the hw completion. The poller takes the mbox_mutex to stabilize the flagging, minimizing any runtime overhead in the send path to check for 'sanitize_tmo' for uncommon poll scenarios. The irq case is much simpler as hardware will serialize/error appropriately. Reviewed-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Davidlohr Bueso <dave@stgolabs.net> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://lore.kernel.org/r/20230612181038.14421-4-dave@stgolabs.net Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-06-25cxl/mem: Introduce security state sysfs fileDavidlohr Bueso
Add a read-only sysfs file to display the security state of a device (currently only pmem): /sys/bus/cxl/devices/memX/security/state This introduces a cxl_security_state structure that is to be the placeholder for common CXL security features. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Fan Ni <fan.ni@samsung.com> Signed-off-by: Davidlohr Bueso <dave@stgolabs.net> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/20230612181038.14421-3-dave@stgolabs.net Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-06-25cxl/memdev: Formalize endpoint port linkageDan Williams
Move the endpoint port that the cxl_mem driver establishes from drvdata to a first class attribute. This is in preparation for device-memory drivers reusing the CXL core for memory region management. Those drivers need a type-safe method to retrieve their CXL port linkage. Leave drvdata for private usage of the cxl_mem driver not external consumers of a 'struct cxl_memdev' object. Reviewed-by: Fan Ni <fan.ni@samsung.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/168679264292.3436160.3901392135863405807.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-06-25cxl/memdev: Make mailbox functionality optionalDan Williams
In support of the Linux CXL core scaling for a wider set of CXL devices, allow for the creation of memdevs with some memory device capabilities disabled. Specifically, allow for CXL devices outside of those claiming to be compliant with the generic CXL memory device class code, like vendor specific Type-2/3 devices that host CXL.mem. This implies, allow for the creation of memdevs that only support component-registers, not necessarily memory-device-registers (like mailbox registers). A memdev derived from a CXL endpoint that does not support generic class code expectations is tagged "CXL_DEVTYPE_DEVMEM", while a memdev derived from a class-code compliant endpoint is tagged "CXL_DEVTYPE_CLASSMEM". The primary assumption of a CXL_DEVTYPE_DEVMEM memdev is that it optionally may not host a mailbox. Disable the command passthrough ioctl for memdevs that are not CXL_DEVTYPE_CLASSMEM, and return empty strings from memdev attributes associated with data retrieved via the class-device-standard IDENTIFY command. Note that empty strings were chosen over attribute visibility to maintain compatibility with shipping versions of cxl-cli that expect those attributes to always be present. Once cxl-cli has dropped that requirement this workaround can be deprecated. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/168679260782.3436160.7587293613945445365.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-06-25cxl/mbox: Move mailbox related driver state to its own data structureDan Williams
'struct cxl_dev_state' makes too many assumptions about the capabilities of a CXL device. In particular it assumes a CXL device has a mailbox and all of the infrastructure and state that comes along with that. In preparation for supporting accelerator / Type-2 devices that may not have a mailbox and in general maintain a minimal core context structure, make mailbox functionality a super-set of 'struct cxl_dev_state' with 'struct cxl_memdev_state'. With this reorganization it allows for CXL devices that support HDM decoder mapping, but not other general-expander / Type-3 capabilities, to only enable that subset without the rest of the mailbox infrastructure coming along for the ride. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/168679260240.3436160.15520641540463704524.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-04-23cxl/memdev: Trace inject and clear poison as cxl_poison eventsAlison Schofield
The cxl_poison trace event allows users to view the history of poison list reads. With the addition of inject and clear poison capabilities, users will expect similar tracing. Add trace types 'Inject' and 'Clear' to the cxl_poison trace_event and trace successful operations only. If the driver finds that the DPA being injected or cleared of poison is mapped in a region, that region info is included in the cxl_poison trace event. Region reconfigurations can make this extra info useless if the debug operations are not carefully managed. Signed-off-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/e20eb7c3029137b480ece671998c183da0477e2e.1681874357.git.alison.schofield@intel.com Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-04-23cxl/memdev: Warn of poison inject or clear to a mapped regionAlison Schofield
Inject and clear poison capabilities and intended for debug usage only. In order to be useful in debug environments, the driver needs to allow inject and clear operations on DPAs mapped in regions. dev_warn_once() when either operation occurs. Signed-off-by: Alison Schofield <alison.schofield@intel.com> Link: https://lore.kernel.org/r/f911ca5277c9d0f9757b72d7e6842871bfff4fa2.1681874357.git.alison.schofield@intel.com Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-04-23cxl/memdev: Add support for the Clear Poison mailbox commandAlison Schofield
CXL devices optionally support the CLEAR POISON mailbox command. Add memdev driver support for clearing poison. Per the CXL Specification (3.0 8.2.9.8.4.3), after receiving a valid clear poison request, the device removes the address from the device's Poison List and writes 0 (zero) for 64 bytes starting at address. If the device cannot clear poison from the address, it returns a permanent media error and -ENXIO is returned to the user. Additionally, and per the spec also, it is not an error to clear poison of an address that is not poisoned. If the address is not contained in the device's dpa resource, or is not 64 byte aligned, the driver returns -EINVAL without sending the command to the device. Poison clearing is intended for debug only and will be exposed to userspace through debugfs. Restrict compilation to CONFIG_DEBUG_FS. Implementation note: Although the CXL specification defines the clear command to accept 64 bytes of 'write-data', this implementation always uses zeroes as write-data. Signed-off-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://lore.kernel.org/r/8682c30ec24bd9c45af5feccb04b02be51e58c0a.1681874357.git.alison.schofield@intel.com Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-04-23cxl/memdev: Add support for the Inject Poison mailbox commandAlison Schofield
CXL devices optionally support the INJECT POISON mailbox command. Add memdev driver support for the mailbox command. Per the CXL Specification (3.0 8.2.9.8.4.2), after receiving a valid inject poison request, the device will return poison when the address is accessed through the CXL.mem driver. Injecting poison adds the address to the device's Poison List and the error source is set to Injected. In addition, the device adds a poison creation event to its internal Informational Event log, updates the Event Status register, and if configured, interrupts the host. Also, per the CXL Specification, it is not an error to inject poison into an address that already has poison present and no error is returned from the device. If the address is not contained in the device's dpa resource, or is not 64 byte aligned, return -EINVAL without issuing the mbox command. Poison injection is intended for debug only and will be exposed to userspace through debugfs. Restrict compilation to CONFIG_DEBUG_FS. Signed-off-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/241c64115e6bd2effed9c7a20b08b3908dd7be8f.1681874357.git.alison.schofield@intel.com Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-04-23cxl/region: Provide region info to the cxl_poison trace eventAlison Schofield
User space may need to know which region, if any, maps the poison address(es) logged in a cxl_poison trace event. Since the mapping of DPAs (device physical addresses) to a region can change, the kernel must provide this information at the time the poison list is read. The event informs user space that at event <timestamp> this <region> mapped to this <DPA>, which is poisoned. The cxl_poison trace event is already wired up to log the region name and uuid if it receives param 'struct cxl_region'. In order to provide that cxl_region, add another method for gathering poison - by committed endpoint decoder mappings. This method is only available with CONFIG_CXL_REGION and is only used if a region actually maps the memdev where poison is being read. After the region driver reads the poison list for all the mapped resources, poison is read for any remaining unmapped resources. The default method remains: read the poison by memdev resource. Signed-off-by: Alison Schofield <alison.schofield@intel.com> Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/438b01ccaa70592539e8eda4eb2b1d617ba03160.1681838292.git.alison.schofield@intel.com Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-04-23cxl/memdev: Add trigger_poison_list sysfs attributeAlison Schofield
When a boolean 'true' is written to this attribute the memdev driver retrieves the poison list from the device. The list consists of addresses that are poisoned, or would result in poison if accessed, and the source of the poison. This attribute is only visible for devices supporting the capability. The retrieved errors are logged as kernel events when cxl_poison event tracing is enabled. Signed-off-by: Alison Schofield <alison.schofield@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Ira Weiny <ira.weiny@intel.com> Link: https://lore.kernel.org/r/1081cfdc8a349dc754779642d584707e56db26ba.1681838291.git.alison.schofield@intel.com Tested-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-02-25Merge tag 'cxl-for-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxlLinus Torvalds
Pull Compute Express Link (CXL) updates from Dan Williams: "To date Linux has been dependent on platform-firmware to map CXL RAM regions and handle events / errors from devices. With this update we can now parse / update the CXL memory layout, and report events / errors from devices. This is a precursor for the CXL subsystem to handle the end-to-end "RAS" flow for CXL memory. i.e. the flow that for DDR-attached-DRAM is handled by the EDAC driver where it maps system physical address events to a field-replaceable-unit (FRU / endpoint device). In general, CXL has the potential to standardize what has historically been a pile of memory-controller-specific error handling logic. Another change of note is the default policy for handling RAM-backed device-dax instances. Previously the default access mode was "device", mmap(2) a device special file to access memory. The new default is "kmem" where the address range is assigned to the core-mm via add_memory_driver_managed(). This saves typical users from wondering why their platform memory is not visible via free(1) and stuck behind a device-file. At the same time it allows expert users to deploy policy to, for example, get dedicated access to high performance memory, or hide low performance memory from general purpose kernel allocations. This affects not only CXL, but also systems with high-bandwidth-memory that platform-firmware tags with the EFI_MEMORY_SP (special purpose) designation. Summary: - CXL RAM region enumeration: instantiate 'struct cxl_region' objects for platform firmware created memory regions - CXL RAM region provisioning: complement the existing PMEM region creation support with RAM region support - "Soft Reservation" policy change: Online (memory hot-add) soft-reserved memory (EFI_MEMORY_SP) by default, but still allow for setting aside such memory for dedicated access via device-dax. - CXL Events and Interrupts: Takeover CXL event handling from platform-firmware (ACPI calls this CXL Memory Error Reporting) and export CXL Events via Linux Trace Events. - Convey CXL _OSC results to drivers: Similar to PCI, let the CXL subsystem interrogate the result of CXL _OSC negotiation. - Emulate CXL DVSEC Range Registers as "decoders": Allow for first-generation devices that pre-date the definition of the CXL HDM Decoder Capability to translate the CXL DVSEC Range Registers into 'struct cxl_decoder' objects. - Set timestamp: Per spec, set the device timestamp in case of hotplug, or if platform-firwmare failed to set it. - General fixups: linux-next build issues, non-urgent fixes for pre-production hardware, unit test fixes, spelling and debug message improvements" * tag 'cxl-for-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl: (66 commits) dax/kmem: Fix leak of memory-hotplug resources cxl/mem: Add kdoc param for event log driver state cxl/trace: Add serial number to trace points cxl/trace: Add host output to trace points cxl/trace: Standardize device information output cxl/pci: Remove locked check for dvsec_range_allowed() cxl/hdm: Add emulation when HDM decoders are not committed cxl/hdm: Create emulated cxl_hdm for devices that do not have HDM decoders cxl/hdm: Emulate HDM decoder from DVSEC range registers cxl/pci: Refactor cxl_hdm_decode_init() cxl/port: Export cxl_dvsec_rr_decode() to cxl_port cxl/pci: Break out range register decoding from cxl_hdm_decode_init() cxl: add RAS status unmasking for CXL cxl: remove unnecessary calling of pci_enable_pcie_error_reporting() dax/hmem: build hmem device support as module if possible dax: cxl: add CXL_REGION dependency cxl: avoid returning uninitialized error code cxl/pmem: Fix nvdimm registration races cxl/mem: Fix UAPI command comment cxl/uapi: Tag commands from cxl_query_cmd() ...
2023-02-10Merge branch 'for-6.3/cxl-ram-region' into cxl/nextDan Williams
Include the support for enumerating and provisioning ram regions for v6.3. This also include a default policy change for ram / volatile device-dax instances to assign them to the dax_kmem driver by default.
2023-02-10cxl/memdev: Fix endpoint port removalDan Williams
Testing of ram region support [1], stimulates a long standing bug in cxl_detach_ep() where some cxl_ep_remove() cleanup is skipped due to inability to walk ports after dports have been unregistered. That results in a failure to re-register a memdev after the port is re-enabled leading to a crash like the following: cxl_port_setup_targets: cxl region4: cxl_host_bridge.0:port4 iw: 1 ig: 256 general protection fault, ... [..] RIP: 0010:cxl_region_setup_targets+0x897/0x9e0 [cxl_core] dev_name at include/linux/device.h:700 (inlined by) cxl_port_setup_targets at drivers/cxl/core/region.c:1155 (inlined by) cxl_region_setup_targets at drivers/cxl/core/region.c:1249 [..] Call Trace: <TASK> attach_target+0x39a/0x760 [cxl_core] ? __mutex_unlock_slowpath+0x3a/0x290 cxl_add_to_region+0xb8/0x340 [cxl_core] ? lockdep_hardirqs_on+0x7d/0x100 discover_region+0x4b/0x80 [cxl_port] ? __pfx_discover_region+0x10/0x10 [cxl_port] device_for_each_child+0x58/0x90 cxl_port_probe+0x10e/0x130 [cxl_port] cxl_bus_probe+0x17/0x50 [cxl_core] Change the port ancestry walk to be by depth rather than by dport. This ensures that even if a port has unregistered its dports a deferred memdev cleanup will still be able to cleanup the memdev's interest in that port. The parent_port->dev.driver check is only needed for determining if the bottom up removal beat the top-down removal, but cxl_ep_remove() can always proceed given the port is pinned. That is, the two sources of cxl_ep_remove() are in cxl_detach_ep() and cxl_port_release(), and cxl_port_release() can not run if cxl_detach_ep() holds a reference. Fixes: 2703c16c75ae ("cxl/core/port: Add switch port enumeration") Link: http://lore.kernel.org/r/167564534874.847146.5222419648551436750.stgit@dwillia2-xfh.jf.intel.com [1] Reviewed-by: Vishal Verma <vishal.l.verma@intel.com> Link: https://lore.kernel.org/r/167601992789.1924368.8083994227892600608.stgit@dwillia2-xfh.jf.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-02-09cxl/mem: Correct full ID range allocationDavidlohr Bueso
For ID allocations we want 0-(max-1), ie: smatch complains: error: Calling ida_alloc_range() with a 'max' argument which is a power of 2. -1 missing? Correct this and also replace the call to use the max() flavor instead. Signed-off-by: Davidlohr Bueso <dave@stgolabs.net> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/20230208181944.240261-1-dave@stgolabs.net Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2023-01-27driver core: make struct bus_type.uevent() take a const *Greg Kroah-Hartman
The uevent() callback in struct bus_type should not be modifying the device that is passed into it, so mark it as a const * and propagate the function signature changes out into all relevant subsystems that use this callback. Acked-by: Rafael J. Wysocki <rafael@kernel.org> Acked-by: Hans de Goede <hdegoede@redhat.com> Link: https://lore.kernel.org/r/20230111113018.459199-16-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-27driver core: make struct device_type.devnode() take a const *Greg Kroah-Hartman
The devnode() callback in struct device_type should not be modifying the device that is passed into it, so mark it as a const * and propagate the function signature changes out into all relevant subsystems that use this callback. Cc: Jens Axboe <axboe@kernel.dk> Cc: Alison Schofield <alison.schofield@intel.com> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Ben Widawsky <bwidawsk@kernel.org> Cc: Jeremy Kerr <jk@ozlabs.org> Cc: Joel Stanley <joel@jms.id.au> Cc: Alistar Popple <alistair@popple.id.au> Cc: Eddie James <eajames@linux.ibm.com> Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com> Cc: Jilin Yuan <yuanjilin@cdjrlc.com> Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Cc: Won Chung <wonchung@google.com> Acked-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Acked-by: Hans de Goede <hdegoede@redhat.com> Link: https://lore.kernel.org/r/20230111113018.459199-7-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-12-03cxl/pci: Add (hopeful) error handling supportDan Williams
Add nominal error handling that tears down CXL.mem in response to error notifications that imply a device reset. Given some CXL.mem may be operating as System RAM, there is a high likelihood that these error events are fatal. However, if the system survives the notification the expectation is that the driver behavior is equivalent to a hot-unplug and re-plug of an endpoint. Note that this does not change the mask values from the default. That awaits CXL _OSC support to determine whether platform firmware is in control of the mask registers. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Dave Jiang <dave.jiang@intel.com> Link: https://lore.kernel.org/r/166974413966.1608150.15522782911404473932.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2022-07-09cxl/mem: Convert partition-info to resourcesDan Williams
To date the per-device-partition DPA range information has only been used for enumeration purposes. In preparation for allocating regions from available DPA capacity, convert those ranges into DPA-type resource trees. With resources and the new add_dpa_res() helper some open coded end address calculations and debug prints can be cleaned. The 'cxlds->pmem_res' and 'cxlds->ram_res' resources are child resources of the total-device DPA space and they in turn will host DPA allocations from cxl_endpoint_decoder instances (tracked by cxled->dpa_res). Cc: Ira Weiny <ira.weiny@intel.com> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://lore.kernel.org/r/165603878921.551046.8127845916514734142.stgit@dwillia2-xfh Signed-off-by: Dan Williams <dan.j.williams@intel.com>