[PATCH v2 4/4] fs: remove fs_lookup_param and its description.

[Hongbo Li <lihongbo22@huawei.com>]

After `fs_param_is_blockdev` and `fs_param_is_path` are implemented,
there are no need to lookup the path with `fs_lookup_param`, and
`fs_parse` is sufficient.

Signed-off-by: Hongbo Li <lihongbo22@huawei.com>
---
 Documentation/filesystems/mount_api.rst | 17 +-------
 fs/fs_parser.c                          | 56 -------------------------
 include/linux/fs_parser.h               |  6 ---
 3 files changed, 1 insertion(+), 78 deletions(-)

diff --git a/Documentation/filesystems/mount_api.rst b/Documentation/filesystems/mount_api.rst
index 9aaf6ef75eb5..f92d96758e57 100644
--- a/Documentation/filesystems/mount_api.rst
+++ b/Documentation/filesystems/mount_api.rst
@@ -253,7 +253,7 @@ manage the filesystem context.  They are as follows:
      will have been weeded out and fc->sb_flags updated in the context.
      Security options will also have been weeded out and fc->security updated.
 
-     The parameter can be parsed with fs_parse() and fs_lookup_param().  Note
+     The parameter can be parsed with fs_parse().  Note
      that the source(s) are presented as parameters named "source".
 
      If successful, 0 should be returned or a negative error code otherwise.
@@ -796,18 +796,3 @@ process the parameters it is given.
      If the parameter isn't matched, -ENOPARAM will be returned; if the
      parameter is matched, but the value is erroneous, -EINVAL will be
      returned; otherwise the parameter's option number will be returned.
-
-   * ::
-
-       int fs_lookup_param(struct fs_context *fc,
-			   struct fs_parameter *value,
-			   bool want_bdev,
-			   unsigned int flags,
-			   struct path *_path);
-
-     This takes a parameter that carries a string or filename type and attempts
-     to do a path lookup on it.  If the parameter expects a blockdev, a check
-     is made that the inode actually represents one.
-
-     Returns 0 if successful and ``*_path`` will be set; returns a negative
-     error code if not.
diff --git a/fs/fs_parser.c b/fs/fs_parser.c
index 5d0adcc514d8..962adb1fec80 100644
--- a/fs/fs_parser.c
+++ b/fs/fs_parser.c
@@ -133,62 +133,6 @@ int __fs_parse(struct p_log *log,
 }
 EXPORT_SYMBOL(__fs_parse);
 
-/**
- * fs_lookup_param - Look up a path referred to by a parameter
- * @fc: The filesystem context to log errors through.
- * @param: The parameter.
- * @want_bdev: T if want a blockdev
- * @flags: Pathwalk flags passed to filename_lookup()
- * @_path: The result of the lookup
- */
-int fs_lookup_param(struct fs_context *fc,
-		    struct fs_parameter *param,
-		    bool want_bdev,
-		    unsigned int flags,
-		    struct path *_path)
-{
-	struct filename *f;
-	bool put_f;
-	int ret;
-
-	switch (param->type) {
-	case fs_value_is_string:
-		f = getname_kernel(param->string);
-		if (IS_ERR(f))
-			return PTR_ERR(f);
-		put_f = true;
-		break;
-	case fs_value_is_filename:
-		f = param->name;
-		put_f = false;
-		break;
-	default:
-		return invalf(fc, "%s: not usable as path", param->key);
-	}
-
-	ret = filename_lookup(param->dirfd, f, flags, _path, NULL);
-	if (ret < 0) {
-		errorf(fc, "%s: Lookup failure for '%s'", param->key, f->name);
-		goto out;
-	}
-
-	if (want_bdev &&
-	    !S_ISBLK(d_backing_inode(_path->dentry)->i_mode)) {
-		path_put(_path);
-		_path->dentry = NULL;
-		_path->mnt = NULL;
-		errorf(fc, "%s: Non-blockdev passed as '%s'",
-		       param->key, f->name);
-		ret = -ENOTBLK;
-	}
-
-out:
-	if (put_f)
-		putname(f);
-	return ret;
-}
-EXPORT_SYMBOL(fs_lookup_param);
-
 static int fs_param_bad_value(struct p_log *log, struct fs_parameter *param)
 {
 	return inval_plog(log, "Bad value for '%s'", param->key);
diff --git a/include/linux/fs_parser.h b/include/linux/fs_parser.h
index 489c71d06a5f..fa2745254818 100644
--- a/include/linux/fs_parser.h
+++ b/include/linux/fs_parser.h
@@ -74,12 +74,6 @@ static inline int fs_parse(struct fs_context *fc,
 	return __fs_parse(&fc->log, desc, param, result);
 }
 
-extern int fs_lookup_param(struct fs_context *fc,
-			   struct fs_parameter *param,
-			   bool want_bdev,
-			   unsigned int flags,
-			   struct path *_path);
-
 extern int lookup_constant(const struct constant_table tbl[], const char *name, int not_found);
 
 #ifdef CONFIG_VALIDATE_FS_PARSER
-- 
2.34.1