The UBIFS_DFS_DIR_LEN macro, which defines the maximum length of the UBIFS
debugfs directory name, has an incorrect formula and misleading comments.
The current formula is (3 + 1 + 2*2 + 1), which assumes that both UBI device
number and volume ID are limited to 2 characters. However, UBI device number
ranges from 0 to 31 (2 characters), and volume ID ranges from 0 to 127 (up
to 3 characters).
Although the current code works due to the cancellation of mathematical
errors (9 + 1 = 10, which matches the correct UBIFS_DFS_DIR_LEN value), it
can lead to confusion and potential issues in the future.
This patch aims to improve the code clarity and maintainability by making
the following changes:
1. Corrects the UBIFS_DFS_DIR_LEN macro definition to (3 + 1 + 2 + 3 + 1),
accommodating the maximum lengths of both UBI device number and volume ID,
plus the separators and null terminator.
2. Updates the snprintf calls to use UBIFS_DFS_DIR_LEN instead of
UBIFS_DFS_DIR_LEN + 1, removing the unnecessary +1.
3. Modifies the error checks to compare against UBIFS_DFS_DIR_LEN using >=
instead of >, aligning with the corrected macro definition.
4. Removes the redundant +1 in the dfs_dir_name array definitions in ubi.h
and debug.h.
While these changes do not affect the runtime behavior, they make the code
more readable, maintainable, and less prone to future errors.
v2->v3:
- Removes the duplicated UBIFS_DFS_DIR_LEN and UBIFS_DFS_DIR_NAME macro
definitions in ubifs.h, as they are already defined in debug.h.
Signed-off-by: ZhaoLong Wang <wangzhaolong1@huawei.com>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Since commit ee6d3dd4ed ("driver core: make kobj_type constant.")
the driver core allows the usage of const struct kobj_type.
Take advantage of this to constify the structure definitions to prevent
modification at runtime.
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
There are currently 2 ways to create a set of sysfs files for a
kobj_type, through the default_attrs field, and the default_groups
field. Move the ubifs sysfs code to use default_groups field which has
been the preferred way since aa30f47cf6 ("kobject: Add support for
default attribute groups to kobj_type") so that we can soon get rid of
the obsolete default_attrs field.
Cc: Stefan Schaeckeler <schaecsn@gmx.net>
Cc: linux-mtd@lists.infradead.org
Acked-by: Richard Weinberger <richard@nod.at>
Link: https://lore.kernel.org/r/20220114104820.1340879-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The snprintf() function returns the number of bytes (not including the
NUL terminator) which would have been printed if there were enough
space. So it can be greater than UBIFS_DFS_DIR_LEN. And actually if
it equals UBIFS_DFS_DIR_LEN then that's okay so this check is too
strict.
Fixes: 9a620291fc01 ("ubifs: Export filesystem error counters")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Not all ubifs filesystem errors are propagated to userspace.
Export bad magic, bad node and crc errors via sysfs. This allows userspace
to notice filesystem errors:
/sys/fs/ubifs/ubiX_Y/errors_magic
/sys/fs/ubifs/ubiX_Y/errors_node
/sys/fs/ubifs/ubiX_Y/errors_crc
The counters are reset to 0 with a remount.
Signed-off-by: Stefan Schaeckeler <sschaeck@cisco.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
