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Dan Williams 8e4c411c53 cxl: Introduce 'struct cxl_dpa_partition' and 'struct cxl_range_info'
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>
2025-02-04 13:48:19 -07:00
arch sh updates for v6.14 2025-02-02 10:40:27 -08:00
block block-6.14-20250131 2025-01-31 11:49:30 -08:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
Documentation 21 hotfixes. 8 are cc:stable and the remainder address post-6.13 issues. 2025-02-01 09:49:20 -08:00
drivers cxl: Introduce 'struct cxl_dpa_partition' and 'struct cxl_range_info' 2025-02-04 13:48:19 -07:00
fs assorted stuff for this merge window 2025-02-01 15:07:56 -08:00
include assorted stuff for this merge window 2025-02-01 15:07:56 -08:00
init Kbuild updates for v6.14 2025-01-31 12:07:07 -08:00
io_uring io_uring-6.14-20250131 2025-01-31 11:29:23 -08:00
ipc treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
kernel 21 hotfixes. 8 are cc:stable and the remainder address post-6.13 issues. 2025-02-01 09:49:20 -08:00
lib 21 hotfixes. 8 are cc:stable and the remainder address post-6.13 issues. 2025-02-01 09:49:20 -08:00
LICENSES LICENSES: add 0BSD license text 2024-09-01 20:43:24 -07:00
mm assorted stuff for this merge window 2025-02-01 15:07:56 -08:00
net assorted stuff for this merge window 2025-02-01 15:07:56 -08:00
rust Kbuild updates for v6.14 2025-01-31 12:07:07 -08:00
samples AT_EXECVE_CHECK update for v6.14-rc1 (fix1) 2025-01-31 17:12:31 -08:00
scripts 21 hotfixes. 8 are cc:stable and the remainder address post-6.13 issues. 2025-02-01 09:49:20 -08:00
security treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
sound sound fixes for 6.14-rc1 2025-01-31 09:17:02 -08:00
tools cxl: Introduce 'struct cxl_dpa_partition' and 'struct cxl_range_info' 2025-02-04 13:48:19 -07:00
usr kbuild: Drop support for include/asm-<arch> in headers_check.pl 2024-12-21 11:43:17 +09:00
virt Merge branch 'kvm-mirror-page-tables' into HEAD 2025-01-20 07:15:58 -05:00
.clang-format clang-format: Update with v6.11-rc1's for_each macro list 2024-08-02 13:20:31 +02:00
.clippy.toml rust: give Clippy the minimum supported Rust version 2025-01-10 00:17:25 +01:00
.cocciconfig
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore MAINTAINERS: Retire Ralf Baechle 2024-11-12 15:48:59 +01:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore rust: use host dylib naming convention to support macOS 2025-01-10 01:01:24 +01:00
.mailmap 21 hotfixes. 8 are cc:stable and the remainder address post-6.13 issues. 2025-02-01 09:49:20 -08:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS Mainly individually changelogged singleton patches. The patch series in 2025-01-26 17:50:53 -08:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS 21 hotfixes. 8 are cc:stable and the remainder address post-6.13 issues. 2025-02-01 09:49:20 -08:00
Makefile Linux 6.14-rc1 2025-02-02 15:39:26 -08:00
README README: Fix spelling 2024-03-18 03:36:32 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.