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author | Michael Ellerman <michael@ellerman.id.au> | 2006-03-07 21:41:59 +1100 |
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committer | Greg Kroah-Hartman <gregkh@suse.de> | 2006-03-20 13:42:59 -0800 |
commit | dd308bc355a1aa4f202fe9a3133b6c676cb9606c (patch) | |
tree | accab2f0576da81d5e0ccfdbcc07f25a2a232008 /fs/debugfs | |
parent | c516865cfbac0d862d4888df91793ad1e74ffd58 (diff) | |
download | kernel_samsung_tuna-dd308bc355a1aa4f202fe9a3133b6c676cb9606c.zip kernel_samsung_tuna-dd308bc355a1aa4f202fe9a3133b6c676cb9606c.tar.gz kernel_samsung_tuna-dd308bc355a1aa4f202fe9a3133b6c676cb9606c.tar.bz2 |
[PATCH] debugfs: Add debugfs_create_blob() helper for exporting binary data
I wanted to export a binary blob via debugfs, and although it was pretty easy
it seems like it'd be easier if there was a helper for it. It's a pity we need
the wrapper struct but I can't see a cleaner way to do it.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'fs/debugfs')
-rw-r--r-- | fs/debugfs/file.c | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/fs/debugfs/file.c b/fs/debugfs/file.c index d575452..40c4fc9 100644 --- a/fs/debugfs/file.c +++ b/fs/debugfs/file.c @@ -251,3 +251,49 @@ struct dentry *debugfs_create_bool(const char *name, mode_t mode, } EXPORT_SYMBOL_GPL(debugfs_create_bool); +static ssize_t read_file_blob(struct file *file, char __user *user_buf, + size_t count, loff_t *ppos) +{ + struct debugfs_blob_wrapper *blob = file->private_data; + return simple_read_from_buffer(user_buf, count, ppos, blob->data, + blob->size); +} + +static struct file_operations fops_blob = { + .read = read_file_blob, + .open = default_open, +}; + +/** + * debugfs_create_blob - create a file in the debugfs filesystem that is + * used to read and write a binary blob. + * + * @name: a pointer to a string containing the name of the file to create. + * @mode: the permission that the file should have + * @parent: a pointer to the parent dentry for this file. This should be a + * directory dentry if set. If this paramater is NULL, then the + * file will be created in the root of the debugfs filesystem. + * @blob: a pointer to a struct debugfs_blob_wrapper which contains a pointer + * to the blob data and the size of the data. + * + * This function creates a file in debugfs with the given name that exports + * @blob->data as a binary blob. If the @mode variable is so set it can be + * read from. Writing is not supported. + * + * This function will return a pointer to a dentry if it succeeds. This + * pointer must be passed to the debugfs_remove() function when the file is + * to be removed (no automatic cleanup happens if your module is unloaded, + * you are responsible here.) If an error occurs, NULL will be returned. + * + * If debugfs is not enabled in the kernel, the value -ENODEV will be + * returned. It is not wise to check for this value, but rather, check for + * NULL or !NULL instead as to eliminate the need for #ifdef in the calling + * code. + */ +struct dentry *debugfs_create_blob(const char *name, mode_t mode, + struct dentry *parent, + struct debugfs_blob_wrapper *blob) +{ + return debugfs_create_file(name, mode, parent, blob, &fops_blob); +} +EXPORT_SYMBOL_GPL(debugfs_create_blob); |