linux/include/linux/fs_context.h

/* SPDX-License-Identifier: GPL-2.0-or-later */
/* Filesystem superblock creation and reconfiguration context.
 *
 * Copyright (C) 2018 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells ([email protected])
 */

#ifndef _LINUX_FS_CONTEXT_H
#define _LINUX_FS_CONTEXT_H

#include <linux/kernel.h>
#include <linux/refcount.h>
#include <linux/errno.h>
#include <linux/security.h>
#include <linux/mutex.h>

struct cred;
struct dentry;
struct file_operations;
struct file_system_type;
struct mnt_namespace;
struct net;
struct pid_namespace;
struct super_block;
struct user_namespace;
struct vfsmount;
struct path;

enum fs_context_purpose { … };

/*
 * Userspace usage phase for fsopen/fspick.
 */
enum fs_context_phase { … };

/*
 * Type of parameter value.
 */
enum fs_value_type { … };

/*
 * Configuration parameter.
 */
struct fs_parameter { … };

struct p_log { … };

/*
 * Filesystem context for holding the parameters used in the creation or
 * reconfiguration of a superblock.
 *
 * Superblock creation fills in ->root whereas reconfiguration begins with this
 * already set.
 *
 * See Documentation/filesystems/mount_api.rst
 */
struct fs_context { … };

struct fs_context_operations { … };

/*
 * fs_context manipulation functions.
 */
extern struct fs_context *fs_context_for_mount(struct file_system_type *fs_type,
						unsigned int sb_flags);
extern struct fs_context *fs_context_for_reconfigure(struct dentry *dentry,
						unsigned int sb_flags,
						unsigned int sb_flags_mask);
extern struct fs_context *fs_context_for_submount(struct file_system_type *fs_type,
						struct dentry *reference);

extern struct fs_context *vfs_dup_fs_context(struct fs_context *fc);
extern int vfs_parse_fs_param(struct fs_context *fc, struct fs_parameter *param);
extern int vfs_parse_fs_string(struct fs_context *fc, const char *key,
			       const char *value, size_t v_size);
int vfs_parse_monolithic_sep(struct fs_context *fc, void *data,
			     char *(*sep)(char **));
extern int generic_parse_monolithic(struct fs_context *fc, void *data);
extern int vfs_get_tree(struct fs_context *fc);
extern void put_fs_context(struct fs_context *fc);
extern int vfs_parse_fs_param_source(struct fs_context *fc,
				     struct fs_parameter *param);
extern void fc_drop_locked(struct fs_context *fc);
int reconfigure_single(struct super_block *s,
		       int flags, void *data);

extern int get_tree_nodev(struct fs_context *fc,
			 int (*fill_super)(struct super_block *sb,
					   struct fs_context *fc));
extern int get_tree_single(struct fs_context *fc,
			 int (*fill_super)(struct super_block *sb,
					   struct fs_context *fc));
extern int get_tree_keyed(struct fs_context *fc,
			 int (*fill_super)(struct super_block *sb,
					   struct fs_context *fc),
			 void *key);

int setup_bdev_super(struct super_block *sb, int sb_flags,
		struct fs_context *fc);
extern int get_tree_bdev(struct fs_context *fc,
			       int (*fill_super)(struct super_block *sb,
						 struct fs_context *fc));

extern const struct file_operations fscontext_fops;

/*
 * Mount error, warning and informational message logging.  This structure is
 * shareable between a mount and a subordinate mount.
 */
struct fc_log { … };

extern __attribute__((format(printf, 4, 5)))
void logfc(struct fc_log *log, const char *prefix, char level, const char *fmt, ...);

#define __logfc(fc, l, fmt, ...) …
#define __plog(p, l, fmt, ...) …
/**
 * infof - Store supplementary informational message
 * @fc: The context in which to log the informational message
 * @fmt: The format string
 *
 * Store the supplementary informational message for the process if the process
 * has enabled the facility.
 */
#define infof(fc, fmt, ...) …
#define info_plog(p, fmt, ...) …
#define infofc(p, fmt, ...) …

/**
 * warnf - Store supplementary warning message
 * @fc: The context in which to log the error message
 * @fmt: The format string
 *
 * Store the supplementary warning message for the process if the process has
 * enabled the facility.
 */
#define warnf(fc, fmt, ...) …
#define warn_plog(p, fmt, ...) …
#define warnfc(fc, fmt, ...) …

/**
 * errorf - Store supplementary error message
 * @fc: The context in which to log the error message
 * @fmt: The format string
 *
 * Store the supplementary error message for the process if the process has
 * enabled the facility.
 */
#define errorf(fc, fmt, ...) …
#define error_plog(p, fmt, ...) …
#define errorfc(fc, fmt, ...) …

/**
 * invalf - Store supplementary invalid argument error message
 * @fc: The context in which to log the error message
 * @fmt: The format string
 *
 * Store the supplementary error message for the process if the process has
 * enabled the facility and return -EINVAL.
 */
#define invalf(fc, fmt, ...) …
#define inval_plog(p, fmt, ...) …
#define invalfc(fc, fmt, ...) …

#endif /* _LINUX_FS_CONTEXT_H */