include/linux/kernel_read_file.h

0001 /* SPDX-License-Identifier: GPL-2.0 */
0002 #ifndef _LINUX_KERNEL_READ_FILE_H
0003 #define _LINUX_KERNEL_READ_FILE_H
0004
0005 #include <linux/file.h>
0006 #include <linux/types.h>
0007
0008 /* This is a list of *what* is being read, not *how* nor *where*. */
0009 #define __kernel_read_file_id(id) \
0010     id(UNKNOWN, unknown)        \
0011     id(FIRMWARE, firmware)      \
0012     id(MODULE, kernel-module)       \
0013     id(KEXEC_IMAGE, kexec-image)        \
0014     id(KEXEC_INITRAMFS, kexec-initramfs)    \
0015     id(POLICY, security-policy)     \
0016     id(X509_CERTIFICATE, x509-certificate)  \
0017     id(MAX_ID, )
0018
0019 #define __fid_enumify(ENUM, dummy) READING_ ## ENUM,
0020 #define __fid_stringify(dummy, str) #str,
0021
0022 enum kernel_read_file_id {
0023     __kernel_read_file_id(__fid_enumify)
0024 };
0025
0026 static const char * const kernel_read_file_str[] = {
0027     __kernel_read_file_id(__fid_stringify)
0028 };
0029
0030 static inline const char *kernel_read_file_id_str(enum kernel_read_file_id id)
0031 {
0032     if ((unsigned int)id >= READING_MAX_ID)
0033         return kernel_read_file_str[READING_UNKNOWN];
0034
0035     return kernel_read_file_str[id];
0036 }
0037
0038 ssize_t kernel_read_file(struct file *file, loff_t offset,
0039              void **buf, size_t buf_size,
0040              size_t *file_size,
0041              enum kernel_read_file_id id);
0042 ssize_t kernel_read_file_from_path(const char *path, loff_t offset,
0043                    void **buf, size_t buf_size,
0044                    size_t *file_size,
0045                    enum kernel_read_file_id id);
0046 ssize_t kernel_read_file_from_path_initns(const char *path, loff_t offset,
0047                       void **buf, size_t buf_size,
0048                       size_t *file_size,
0049                       enum kernel_read_file_id id);
0050 ssize_t kernel_read_file_from_fd(int fd, loff_t offset,
0051                  void **buf, size_t buf_size,
0052                  size_t *file_size,
0053                  enum kernel_read_file_id id);
0054
0055 #endif /* _LINUX_KERNEL_READ_FILE_H */