[ndctl PATCH v8 0/7] Add error injection support

[Ben Cheatham <Benjamin.Cheatham@amd.com>]

v8 Changes:
	- Split inject-error command into 'inject-protocol-error', 'inject-media-poison' (Vishal, Alison)
	- Rename 'cxl-clear-error' command to 'cxl-clear-media-poison' (Alison)
	- Documentation rework to reflect new commands
	- Cleaned up a few error prints
	- Updated help messages
	- Change "clear" param of poison_action() to "inj" and reverse usage accordingly
	- Change cxl_memdev_has_poison_injection() to cxl_memdev_has_poison_support()
		- Used in poison_action() (cxl/inject-error.c) to report missing functionality
		more accurately
	- Print usage when '-a' option is missing for media-poison commands
	- Remove checking if '-a' option is empty in poison_action() (no longer needed)
	- Allow clearing poison when 'inject_poison' file is missing in debugfs (and vice versa)
	- Updated cover letter and commit messages

v7 Changes:
	- Use PATH_MAX instead of strlen(ctx->cxl_debugfs) for debugfs paths (Dave)
	- Add goto for error paths to memdev poison functions in patch 3/7 (Dave)
	- Add Dave's Reviewed-by tags

v6 Changes:
	- Rebase to pending branch (Alison)
	- Drop const for ctx->debugfs (Alison)
	- Rename get_debugfs_dir() to get_cxl_debugfs_dir() and return cxl directory in debugfs
	(i.e. "/sys/kernel/debug" -> "/sys/kernel/debug/cxl")
	- Rename ctx->debugfs to ctx->cxl_debugfs
	- Fix missing free of einj path (Alison)
	- Add protocol errors in order to perrors list (Alison)
	- Use hex constants instead of BIT() for protocol errors (Alison)
	- Add symbols to LIBCXL_11 instead of LIBCXL_10 (Alison)
	- Update commit message to reflect util_cxl_dport_filter() behavior (Alison)
	- Remove EINJ_TYPES_BUF_SIZE #ifdef (Alison)
	- Fix type mismatch of addr in poison_action() (Alison)
	- Fix inject_action() to catch missing 'type' option (Alison)
	- Remove '-N' option and show the information behind that option by default when
	CXL debugfs is present (Alison)
	- Add 'protocol_injectable' attribute for dports (Alison)
	- Update inject-error man page with port injection example (Alison)
	- Add warning to inject-error man page (Alison)

v5 Changes:
	- Use setmntent()/getmntent() instead of open-coding getting the
	  debugfs path (Dave)
	- Use correct return code for sysfs_read_attr() (Dave)


This series adds support for injecting CXL protocol (CXL.cache/mem)
errors[1] into CXL RCH Downstream ports and VH root ports[2] and
poison into CXL memory devices through the CXL debugfs. Protocol errors
are injected using a new 'inject-protocol-error' command. Device poison
can be injected and cleared using the 'inject-media-poison' and
'clear-media-poison' commands, respectively. All three commands require
access to the CXL driver's debugfs.

The documentation for the new commands show both usage and the possible
device/error types, as well as how to retrieve them using cxl-list. cxl-list
has been updated to include the possible error types for protocol error
injection (under the "bus" object) and which CXL dports and memory devices
support injection.

[1]: ACPI v6.5 spec, section 18.6.4
[2]: ACPI v6.5 spec, table 18.31

Ben Cheatham (7):
  libcxl: Add debugfs path to CXL context
  libcxl: Add CXL protocol errors
  libcxl: Add poison injection support
  cxl: Add inject-protocol-error command
  cxl: Add poison injection/clear commands
  cxl/list: Add injectable errors in output
  Documentation: Add docs for protocol and poison injection commands

 Documentation/cxl/cxl-clear-media-poison.txt  |  85 +++++
 Documentation/cxl/cxl-inject-media-poison.txt |  85 +++++
 .../cxl/cxl-inject-protocol-error.txt         | 105 ++++++
 Documentation/cxl/meson.build                 |   3 +
 cxl/builtin.h                                 |   3 +
 cxl/cxl.c                                     |   3 +
 cxl/filter.c                                  |  26 ++
 cxl/filter.h                                  |   2 +
 cxl/inject-error.c                            | 312 +++++++++++++++++
 cxl/json.c                                    |  38 ++
 cxl/lib/libcxl.c                              | 329 ++++++++++++++++++
 cxl/lib/libcxl.sym                            |  10 +
 cxl/lib/private.h                             |  14 +
 cxl/libcxl.h                                  |  18 +
 cxl/meson.build                               |   1 +
 15 files changed, 1034 insertions(+)
 create mode 100644 Documentation/cxl/cxl-clear-media-poison.txt
 create mode 100644 Documentation/cxl/cxl-inject-media-poison.txt
 create mode 100644 Documentation/cxl/cxl-inject-protocol-error.txt
 create mode 100644 cxl/inject-error.c

base-commit: 39085f76b6a9d3ac349c3c5dab1cb820c86a293d
-- 
2.52.0