This patch update the Documentation/filesystems/debugfs.txt
file. The main work is to add the description of the following
functions:
debugfs_create_atomic_t
debugfs_create_u32_array
debugfs_create_devm_seqfile
debugfs_create_file_size
Signed-off-by: Wang Long <long.wanglong@huawei.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
The seq_printf() will soon just return void, and seq_has_overflowed()
should be used instead to see if the seq can no longer accept input.
As the return value of debugfs_print_regs32() has no users and
the seq_file descriptor should be checked with seq_has_overflowed()
instead of return values of functions, it is better to just have
debugfs_print_regs32() also return void.
Link: http://lkml.kernel.org/p/2634b19eb1c04a9d31148c1fe6f1f3819be95349.1412031505.git.joe@perches.com
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Joe Perches <joe@perches.com>
[ original change only updated seq_printf() return, added return of
void to debugfs_print_regs32() as well ]
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Since the debugfs is mostly only used by root, make the default mount
mode 0700. Most system owners do not need a more permissive value,
but they can choose to weaken the restrictions via their fstab.
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull vfs pile 1 from Al Viro:
"This is _not_ all; in particular, Miklos' and Jan's stuff is not there
yet."
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (64 commits)
ext4: initialization of ext4_li_mtx needs to be done earlier
debugfs-related mode_t whack-a-mole
hfsplus: add an ioctl to bless files
hfsplus: change finder_info to u32
hfsplus: initialise userflags
qnx4: new helper - try_extent()
qnx4: get rid of qnx4_bread/qnx4_getblk
take removal of PF_FORKNOEXEC to flush_old_exec()
trim includes in inode.c
um: uml_dup_mmap() relies on ->mmap_sem being held, but activate_mm() doesn't hold it
um: embed ->stub_pages[] into mmu_context
gadgetfs: list_for_each_safe() misuse
ocfs2: fix leaks on failure exits in module_init
ecryptfs: make register_filesystem() the last potential failure exit
ntfs: forgets to unregister sysctls on register_filesystem() failure
logfs: missing cleanup on register_filesystem() failure
jfs: mising cleanup on register_filesystem() failure
make configfs_pin_fs() return root dentry on success
configfs: configfs_create_dir() has parent dentry in dentry->d_parent
configfs: sanitize configfs_create()
...
Cautious admins may want to restrict access to debugfs. Currently a
manual chown/chmod e.g. in an init script is needed to achieve that.
Distributions that want to make the mount options configurable need
to add extra config files. By allowing to set the root inode's uid,
gid and mode via mount options no such hacks are needed anymore.
Instead configuration becomes straight forward via fstab.
Signed-off-by: Ludwig Nussel <ludwig.nussel@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (165 commits)
reiserfs: Properly display mount options in /proc/mounts
vfs: prevent remount read-only if pending removes
vfs: count unlinked inodes
vfs: protect remounting superblock read-only
vfs: keep list of mounts for each superblock
vfs: switch ->show_options() to struct dentry *
vfs: switch ->show_path() to struct dentry *
vfs: switch ->show_devname() to struct dentry *
vfs: switch ->show_stats to struct dentry *
switch security_path_chmod() to struct path *
vfs: prefer ->dentry->d_sb to ->mnt->mnt_sb
vfs: trim includes a bit
switch mnt_namespace ->root to struct mount
vfs: take /proc/*/mounts and friends to fs/proc_namespace.c
vfs: opencode mntget() mnt_set_mountpoint()
vfs: spread struct mount - remaining argument of next_mnt()
vfs: move fsnotify junk to struct mount
vfs: move mnt_devname
vfs: move mnt_list to struct mount
vfs: switch pnode.h macros to struct mount *
...
Some debugfs file I deal with are mostly blocks of registers,
i.e. lines of the form "<name> = 0x<value>". Some files are only
registers, some include registers blocks among other material. This
patch introduces data structures and functions to deal with both
cases. I expect more users of this over time.
Signed-off-by: Alessandro Rubini <rubini@gnudd.com>
Acked-by: Giancarlo Asnaghi <giancarlo.asnaghi@st.com>
Cc: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This is an updated document covering the internal API for the debugfs
filesystem. Thanks to Shen Feng for suggesting that I put this text here
and noting that the old LWN version was rather out of date.
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Reported-by: Shen Feng <shen@cn.fujitsu.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
