1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_KERNEL_READ_FILE_H
3#define _LINUX_KERNEL_READ_FILE_H
4
5#include <linux/file.h>
6#include <linux/types.h>
7
8/* This is a list of *what* is being read, not *how* nor *where*. */
9#define __kernel_read_file_id(id) \
10	id(UNKNOWN, unknown)		\
11	id(FIRMWARE, firmware)		\
12	id(MODULE, kernel-module)		\
13	id(KEXEC_IMAGE, kexec-image)		\
14	id(KEXEC_INITRAMFS, kexec-initramfs)	\
15	id(POLICY, security-policy)		\
16	id(X509_CERTIFICATE, x509-certificate)	\
17	id(MAX_ID, )
18
19#define __fid_enumify(ENUM, dummy) READING_ ## ENUM,
20#define __fid_stringify(dummy, str) #str,
21
22enum kernel_read_file_id {
23	__kernel_read_file_id(__fid_enumify)
24};
25
26static const char * const kernel_read_file_str[] = {
27	__kernel_read_file_id(__fid_stringify)
28};
29
30static inline const char *kernel_read_file_id_str(enum kernel_read_file_id id)
31{
32	if ((unsigned int)id >= READING_MAX_ID)
33		return kernel_read_file_str[READING_UNKNOWN];
34
35	return kernel_read_file_str[id];
36}
37
38ssize_t kernel_read_file(struct file *file, loff_t offset,
39			 void **buf, size_t buf_size,
40			 size_t *file_size,
41			 enum kernel_read_file_id id);
42ssize_t kernel_read_file_from_path(const char *path, loff_t offset,
43				   void **buf, size_t buf_size,
44				   size_t *file_size,
45				   enum kernel_read_file_id id);
46ssize_t kernel_read_file_from_path_initns(const char *path, loff_t offset,
47					  void **buf, size_t buf_size,
48					  size_t *file_size,
49					  enum kernel_read_file_id id);
50ssize_t kernel_read_file_from_fd(int fd, loff_t offset,
51				 void **buf, size_t buf_size,
52				 size_t *file_size,
53				 enum kernel_read_file_id id);
54
55#endif /* _LINUX_KERNEL_READ_FILE_H */
56