Commit Graph

6 Commits

Author SHA1 Message Date
Christoph Hellwig b6f8ed33ab pstore/blk: remove {un,}register_pstore_blk
This interface is entirely unused, so remove them and various bits of
unreachable code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20201016132047.3068029-4-hch@lst.de
2020-12-01 12:01:03 -08:00
Christoph Hellwig 45a8af4412 pstore/blk: update the command line example
Use the human readable device name instead of the device number, and
add the required best_effort parameter.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: WeiXiong Liao <gmpy.liaowx@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20201016132047.3068029-3-hch@lst.de
2020-12-01 11:32:55 -08:00
Mauro Carvalho Chehab b30fd8e962 docs: pstore-blk.rst: fix kernel-doc tags
There is currently a problem with kernel-doc tags from blk.c:

	.../Documentation/admin-guide/pstore-blk:239: ./fs/pstore/blk.c:175: WARNING: Duplicate C declaration, also defined in 'admin-guide/pstore-blk'.
	Declaration is 'register_pstore_device'.
	.../Documentation/admin-guide/pstore-blk:239: ./fs/pstore/blk.c:432: WARNING: Duplicate C declaration, also defined in 'admin-guide/pstore-blk'.
	Declaration is 'register_pstore_blk'.
	.../Documentation/admin-guide/pstore-blk:242: ./include/linux/pstore_blk.h:43: WARNING: Duplicate C declaration, also defined in 'admin-guide/pstore-blk'.
	Declaration is 'pstore_device_info'.

Basically, the internal parts is shown with :export:, instead
of :internal:. Yet, there are some other exported docs that
aren't at the document, because they lack :identifiers:.

So, instead, let's just use :export: at the kAPI part of
the documentation.

Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
2020-10-15 07:49:42 +02:00
WeiXiong Liao 78c08247b9 mtd: Support kmsg dumper based on pstore/blk
This introduces mtdpstore, which is similar to mtdoops but more
powerful. It uses pstore/blk, and aims to store panic and oops logs to
a flash partition, where pstore can later read back and present as files
in the mounted pstore filesystem.

To make mtdpstore work, the "blkdev" of pstore/blk should be set
as MTD device name or MTD device number. For more details, see
Documentation/admin-guide/pstore-blk.rst

This solves a number of issues:
- Work duplication: both of pstore and mtdoops do the same job storing
  panic/oops log. They have very similar logic, registering to kmsg
  dumper and storing logs to several chunks one by one.
- Layer violations: drivers should provides methods instead of polices.
  MTD should provide read/write/erase operations, and allow a higher
  level drivers to provide the chunk management, kmsg dump
  configuration, etc.
- Missing features: pstore provides many additional features, including
  presenting the logs as files, logging dump time and count, and
  supporting other frontends like pmsg, console, etc.

Signed-off-by: WeiXiong Liao <liaoweixiong@allwinnertech.com>
Link: https://lore.kernel.org/lkml/20200511233229.27745-11-keescook@chromium.org/
Link: https://lore.kernel.org/r/1589266715-4168-1-git-send-email-liaoweixiong@allwinnertech.com
Signed-off-by: Kees Cook <keescook@chromium.org>
2020-05-31 19:49:01 -07:00
WeiXiong Liao 7dcb7848ba pstore/blk: Support non-block storage devices
Add support for non-block devices (e.g. MTD). A non-block driver calls
pstore_blk_register_device() to register iself.

In addition, pstore/zone is updated to handle non-block devices,
where an erase must be done before a write. Without this, there is no
way to remove records stored to an MTD.

Signed-off-by: WeiXiong Liao <liaoweixiong@allwinnertech.com>
Link: https://lore.kernel.org/lkml/20200511233229.27745-10-keescook@chromium.org/
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
2020-05-31 19:49:00 -07:00
WeiXiong Liao 649304c936 Documentation: Add details for pstore/blk
Add details on using pstore/blk, the new backend of pstore to record
dumps to block devices, in Documentation/admin-guide/pstore-blk.rst

Signed-off-by: WeiXiong Liao <liaoweixiong@allwinnertech.com>
Link: https://lore.kernel.org/lkml/20200511233229.27745-7-keescook@chromium.org/
Signed-off-by: Kees Cook <keescook@chromium.org>
2020-05-30 10:34:03 -07:00